Intermittent Starting Problems & Check Engine Light!!! '91 Previa LE AWD

[Ari]

Hi All,

New (and frustrated) Previa owner here, trying to do a 600km mountain drive home, and my "new" Previa is roflroflroflroflting the bed!


Just bought this 91 awd Previa LE and was warned by owner that it had an intermittent starting problem. Test drove and ran fine, always on/off without problems. 4 days later, problem reared up.

When key is turned it cranks, but no go. Took about 10 minutes of intermittent trying to get it to go - as described by old owner. Then the Check Engine Light came on while highway driving, still ran fine, kept going.

Later on went for a 15 minute drive and on trying to restart after 20 minute stop, it did not start again (while still cranking) but after 10 minutes of trying NO MORE CRANKING (battery still OK)!!! 10 minutes of zero cranking later (and about to call the tow truck), tried it again, and it did crank, and start (Thank Heaven!) and took home.

Taking it to a mechanic today to hook up to diagnostic, looking for any feedback from others who may have had this problem.

Threads I've looked at but not had time to check into (yet) are:
Starting
http://www.ehow.co.uk/how_7915563_tr...ta-previa.html
Good thread - start here - http://www.toyotavanpeople.com/forum...=11&t=7634
http://www.cargurus.com/Cars/Discussion-c4073_ds42438

Check Engine Light
http://www.cargurus.com/Cars/Discussion-t18254_ds498895

Any help would be appreciated. Am stranded in city and unable to go home!!
Ari
Vancouver (for now)

[terbennett]

Not sure exactly what the problem is with yours but I have a 1991 Previa with the same problem. I just had it diagnosed an hour ago and discovered the my issue is a clogged catalytic converter and a flex pipe that needs replacement. The van starts fine when it's cold. However, if it's being started shortly after it's been driven for a while (ie. stopping to fill up), the van doesn't want to start- like it isn't getting any fuel- and I have to wait a few minutes to start it again. Have your exhaust checked out before investing in anything. I just bought a new ignition, starter and fuel pump before discovering this. Foolish me. Those components wouldn't have caused the check engine light to turn on. Now it's in the shop being taken care of.

[timsrv]

Check that fuse box that's part of the positive battery terminal. The ECU gets it's power from a fuse in that box. It's common on the Previa for corrosion to get out of control inside the lower part of the fuse box and cause intermittent problems like you describe. You can't see it because it's got the plastic covers. Pull the plastic covers off and check the conductors inside. Another way to check is to turn the key to the run position but don't start. Look at the dash and you should see the "check engine" light illuminated. This light being illuminated means the ECU has power. If it's out, then the ECU doesn't have power. Regardless of if it's on or off, keep an eye on it and have somebody wiggle that fuse box. If the "check engine" light starts blinking or goes off / on then that's your problem. Tim

PS: Toyota thinks these are worth their weight in gold, so if you need one, try to find a good one at a salvage yard. There are different configurations depending on whether it has ABS or not, so if this is your problem make sure to get the correct fuse box.





Terbennett, the problem you describe doesn't sound like a clogged cat converter. The classic symptoms of a plugged up cat are severe power loss and a melted EGR modulator. In really severe cases the engine will stall (due to extreme back-pressure), but will start back up immediately afterwards. Tim

[Ari]

Hi All,

Well, thanks to not turning the vehicle off for about 11hrs straight, I'm home safe and sound from Vancouver and am about to head down to a mechanic to have a look at some of the issues (loose sway bars, tie rods, bushings, torn CV etc... + of course, the intermittent starting!

I have managed to get into the relay box (?) next to the battery and disassemble/reassemble, and I'm happy to report that it was in MINT shape - no corrosion anywhere!! Please see the photos that I (hope) attached.

So there's a bit more info now than earlier on the intermittent starting.

1st off, the issue only began once the 2nd owner (who I bought the van from) had the original starter replaced. It was replace with a Bosch starter and that's when the symptoms began.
Because this is not a genuine Toyota starter, my thoughts are that it may be faulty, and especially because it has worked SO hard over the last year, perhaps frying the contacts or getting too warm next to the exhaust system and not cooling enough to start after its been running.

Any thoughts?

Going to try to isolate with the mechanic in an hour if we can replicate the issue.

Thanks,
Ari


4hrs later....

Front end issues aside (there's lots of play, I'm going to be replacing a bunch of the bushings, tie rods, links and CVs), the starter is functioning well, so that has now been ruled out. My local mechanic has suggested to go through these checks to isolate the problem:

1 - Check the spark plugs - condition, gaps, that I'm getting spark to each...
2 - Check that there is fuel into the system via the fuel rail...
3 - Check the (new-ish) distributor cap for wear and to see if the Ignitor inside is also new
4 - If all of these things are functioning, then he suggested to check a series of sensors such as:
- crank sensor (if it has one)
- cam shaft sensors
- MAF sensor
- 02 sensors

A list of what has been recently replaced:
- Distributor cap and spark plug wires
- Ignitor Coil
- Fuel filter
- Rear shocks

We don't know if the IGNITOR in the distributor cap was replaced as they are apparently 3-400$ up here in BC.

So, I'm heading back out to pull out the passenger seat and begin the troubleshooting checklist.

If anyone has any thoughts or suggestions, please fire away. The help from the other posts has already been great, and if I'd been spending as much time working on the vehicle as I have on the internet trying to find resources, I'd have the front end done by now!!!

Cheers!
Ari
www.simplydeliciouslodge.com

Toyota lovers...
'86 Tercel Wagon SR5 4X4 manual
'00 Echo 4dr manual
'91 Previa LE AWD auto - brand new to us!

[Ari]

So, 4 more hours later...

I've checked the air filter and it seems good, all of the spark plugs which were evenly worn, no black areas or oily bits at all, and checked that each of the wires going to the plugs were getting spark from the distributor - zap zap zap zap.

I could not check the fuel rail to see if it had fuel because I am not that savvy. I lifted up the drivers seat and looked at the rail that I could see, and there does not seem to be any port on it to check if it is pressurized. Am I being dumb?? Main engine compt.jpg spark plug area.jpg

Speaking of being dumb, above the spark plug area is a rubber hose going up and out towards the drivers compartment. I thought that this might be the fuel line, but when we started the van it blew air. What is this hose line doing? What is its function? See the attached photos... what is this.jpg

Also looked at other posts RE: the EGR valve, and want to find out what its role is, if it is specifically located to the left of the Transmission oil dipstick, and if so, if I need to remove it and clean it up? is this the EGR valve.jpg

I've attached some pics of where I'm at, and sadly, I'm still no closer to figuring out what my intermittent starting problem might be.

Any help is appreciated.

Ari

[timsrv]

That's a real nice looking fusible link box. Based on those pics I'd say it's safe to rule that out. The next thing you'll need to determine is whether it's an electrical issue or a fuel issue. One way to check for this is to wait for it to act up, then take a look at the engine light on the dash to make sure it's on while the key is in the "run" position (engine not running). If that light is on, but it still won't start, at least you'll know the ECU is getting power. If it's off, you should concentrate your efforts on the ECU power circuit & possibly the ECU.

One way to check the fuel system is to crack a fuel line (shortly after cranking) to see if gas squirts out. The gas should be under about 40-50 psi so wear safety goggles and be careful not to let too much out. This can also present a fire hazard so make sure the area is well ventilated and there are no ignition sources in the area. If you can loosen a fitting and not get a noticeable squirt, then it's likely a fuel issue. To further prove this, you can loosen the air intake tube (at the throttle body), squirt a shot of starter fluid in there, then re-attach the tube and try to start. If it fires for a second or 2, then you'll know for sure it's a fuel issue.

If you determine it to be a fuel issue, it could be a failing pump or anything in the fuel pump circuit. The fuel pump is mounted in the tank so it's not real easy to get to. You can test it by opening the little box under the drivers seat and installing a jumper (metal paper clip will work good) between the terminals B+ and FP. After the jumper is in place, turn the key to the "run" position, and you should hear the sound of fuel traveling through the system. If you put your ear to the tank you should also be able to hear the pump running. If you hear the pump running and fuel flowing, try to start it to verify it will run. If it does then I'd strongly suspect the "circuit opening relay". The "circuit opening relay" is what sends power to the fuel pump. It's mounted under the top center dash panel (same area as the fuses) and is plainly marked "circuit opening relay". This can be tested independently, but due to the intermittent nature of the problem I'd probably just replace it with a salvage yard one to rule it out.

I can elaborate more on troubleshooting/testing, and will be happy to do so but you should find out if it's fuel or electrical before I go into more details. Tim

PS: That hose that's disconnected on your valve cover is your PCV hose. That hose being disconnected will create a vacuum leak and will make the van run rough. If run for a long time disconnected it will allow moisture to accumulate in the crank case. It needs to be put back on the PCV valve.

[Ari]

Thursday

Hey Tim,

Thanks a bunch for your time and input, I'm going through what you've posted, and am making headway in some areas, and not in others due to my unfamiliarity with the van, but motors in general as well. I'm far better with wood (as a carpenter) or snow (as a skier) than I am with grease!! Still, it's a fun challenge, and I'm "enjoying" the process. What I wouldn't give for a service manual in laymans terms!

Here's what I've done so far today...

That's a real nice looking fusible link box. Based on those pics I'd say it's safe to rule that out. The next thing you'll need to determine is whether it's an electrical issue or a fuel issue. One way to check for this is to wait for it to act up, then take a look at the engine light on the dash to make sure it's on while the key is in the "run" position. If that light is on, but it still won't start, at least you'll know the ECU is getting power. If it's off, you should concentrate your efforts on the ECU power circuit & possibly the ECU.

Confirmed. The ECU is functioning fine, and staying on with no wavering with the key in "run".

One way to check the fuel system is to crack a fuel line (shortly after cranking) to see if gas squirts out. The gas should be under about 40-50 psi so wear safety goggles and be careful not to let too much out. This can also present a fire hazard so make sure the area is well ventilated and there are no ignition sources in the area. If you can loosen a fitting and not get a noticeable squirt, then it's likely a fuel issue. To further prove this, you can loosen the air intake tube (at the throttle body), squirt a shot of starter fluid in there, then re-attach the tube and try to start. If it fires for a second or 2, then you'll know for sure it's a fuel issue.

This is one that I'm having trouble with, as I don't know where to safely access the fuel line to "crack" it. Are we talking under the van or through the access panels under the front seats? There is one just above the right side spark plugs with a release clip, and I moved the clip and then tried to move the rubber line and it wouldn't budge. Not even a bit. After tracing the lines from the fuel tank to the filter to the engine I didn't really find any except for the one that wouldn't move with an easy looking area to "crack" it. Any advice?? Any chance that you could post me a photo with a screwdriver pointing to where I should be looking, or a good description? I can't find anything online, and I'm hesitant to buy a service manual (the local Toyota dealer said they are obsolete and cannot get me one) because mine is the AWD with ABS and all of the Haynes and Chilton manuals online seem to be for the RWD models only. What a pain in the ass!

If you determine it to be a fuel issue, it could be a failing pump or anything in the fuel pump circuit. The fuel pump is mounted in the tank so it's not real easy to get to. You can test it by opening the little box under the drivers seat and installing a jumper (metal paper clip will work good) between the terminals B+ and FP. After the jumper is in place, turn the key to the "run" position, and you should hear the sound of fuel traveling through the system. If you put your ear to the tank you should also be able to hear the pump running. If you hear the pump running and fuel flowing, try to start it to verify it will run.

I did this, and the fuel pump ran fine, could hear it going, and just to make sure I pulled the paper clip out and the noise stopped. Also took it for 3 short spins today and sure enough, each time after sitting for 10-30 minutes, when I tried to start it would only crank and not go. After sitting for 1 hour or more, it fires up like a champ, every time. Once after 1/2 hour of sitting and checking the ignitor coil (looks new), distributor cap (definitely new), rotor (probably new) I tried to start it just for fun, and it wouldn't run. I tried it a second time giving it gas to the floor and up it went! So maybe a pressure issue?? Advice?

A note on the rotor. It seems to be held on with 2 screws, that were too tight for my to remove without stripping them. I seem to have been told that the ignitor lives "under" the distributor cap and rotor, and it was one of the suspected culprits according to the original (2nd) owner. Any thoughts on that?

If it does then I'd strongly suspect the "circuit opening relay". The "circuit opening relay" is what sends power to the fuel pump. It's mounted under the top center dash panel (same area as the fuses) and is plainly marked "circuit opening relay". This can be tested independently, but due to the intermittent nature of the problem I'd probably just replace it with a salvage yard one to rule it out.

I also had one of these and tried it with both CORs and the van exhibited the same intermittent start problem with either of them in it.

I can elaborate more on troubleshooting/testing, and will be happy to do so but you should find out if it's fuel or electrical before I go into more details. Tim

That would be great, thanks!

PS: That hose that's disconnected on your valve cover is your PCV hose. That hose being disconnected will create a vacuum leak and will make the van run rough. If run for a long time disconnected it will allow moisture to accumulate in the crank case. It needs to be put back on the PCV valve.

Yup, had it off only briefly (1-2secs) with the engine running and since then have put it back on.

So that's where I'm at. I'm giving up for now, and will be gone to our Lodge from the 13-17 of May. When I get back I'll take another crack at it, and start working on the front end mechanical.

Thanks for your help and advice, I can see why people fall in love with these things, if it were running strong 100% of the time it would be sweet. And I think that your lifted van is THE roflroflroflrofl! Wish that I had the mechanical savvy and the tools to pull that off.

One last thing, the mechanic told me that it's running rich. Where is the fuel/air mixer, and is it adjustable by a layperson such as myself?

Cheers!
Ari
www.simplydeliciouslodge.com

[timsrv]

There are a few places to crack a fuel line, but the banjo bolt at the cold start injector is one of the easiest places. See the red arrow on the picture below:


Just put a wrench on it and slowly turn it counter-clockwise. If theres fuel pressure it will start to spray fuel when the bolt loses it's grip.

The igniter is under the driver's seat behind the ECU. It's hidden under a piece of body metal so it's easy to miss.

If the van is running rich the only way to adjust it is to find what sensor is bad and replace it. I'm guessing the primary o2 sensor is toast. Jump the diagnostic terminals TE1 & E1 (same box you jumped the fuel pump) and read the codes. The factory service manual explains how to read codes...........do you have one? If not let me know and I'll post those pages for you. Tim

[Ari]

Thanks a bunch Tim,

I'll look into these issues when I'm back on Tuesday and let you know how it goes.

I don't have a factory service manual, and don't know where to get one. The local Toyota dealer tells me that they are obsolete and unavailable. Any idea where I can find one, or am I just going to have to bug you from time to time for pages???

Also, I came across this post and I wonder if this could be another possible source for my intermittent start problem?

Re: Start problems...
by terbennett » Sat May 31, 2008 8:53 pm

I had the same problem two months ago. I replaced the battery first; Six days later the starter; and the battery terminals four days after that. Two days after the terminals I had the battery cables replaced. I have not had any problems since then. That may not sound bad but Previa battery cables are proprietary. I called so many places trying to locate a set but noone had them. The dealer didn't even have them but they can be ordered for over $500!! I couldn't believe it. I called my mechanic and he was able to replace them for around $400 with labor included. Still that was a lot but he could only locate them OEM. Not only that, he had to wait a day to get them delivered- meaning that my van had to stay overnight at his shop. He cut open my old terminals after rmoving them and there was so much corrosion that I'm surprised my van continued starting for as long as it did. Hopefully that's not the case with yours.

Cheers!
Ari

[timsrv]

Occasionally these service manuals will show up on eBay for under $50. I checked and the cheapest one right now is $72.95 + $7.95 shipping. Here's what eBay currently has: http://shop.ebay.com/i.html?_nkw=199....c0.m270.l1313

In the meantime, here's a couple of pics I took of my 91 service manual:





After you jump between the terminals "E1" & "TE1" with a paper clip, turn all accessories off, then turn the key to the run position (do not start), now count the blinks of the engine light in the instrument cluster. A constant even blinking of "on" then "off" indicates normal. A series of blinks separated by a pause indicates trouble code(s) are stored. In order to read the code(s), you need a service manual (it's like reading Morse code). Multiple codes will be lined up back to back separated by a pause in the blinks. Llamavan made an excellent write-up about reading codes on the earlier vans that you should read. The actual codes for the Previa are different (see pics above) but the principals for reading are the same. Here's a link to that write-up: http://www.toyotavantech.com/forum/c...gons-all-years

Just remember that codes can be stored up from previous issues that may have been addressed (yet codes never cleared). Definitely read what's there before clearing, but to be sure the codes are current, you should then clear them and drive to see which ones come back. To clear them pull the ECU fuse or disconnect the battery for 15 seconds or more.

In your case I'd be particularly interested in codes 12, 13, and 14 as these would indicate a problem with your ignition circuit. Tim

[Ari]

Hi Again,

Just got back from a looooong weekend away, still have not had time to do the recommended checks - but I will, 1st thing tomorrow, I promise!!!

That being said, I just got off the phone with my very trusted backyard mechanic who used to be a Toyota service tech. His 1st and 100% sure response to the issue was "bad/worn contacts in the starter, replace the contacts".

Based on the fact that the intermittent starting only began after the starter was replaced, I'd have to agree with him, in theory.

Any thoughts??

Thanks,
Ari

[djshimon]

check the contacts. why not rule out an easy one?

[timsrv]

When key is turned it cranks, but no go. Took about 10 minutes of intermittent trying to get it to go - as described by old owner. Then the Check Engine Light came on while highway driving, still ran fine, kept going.

Later on went for a 15 minute drive and on trying to restart after 20 minute stop, it did not start again (while still cranking) but after 10 minutes of trying NO MORE CRANKING (battery still OK)!!! 10 minutes of zero cranking later (and about to call the tow truck), tried it again, and it did crank, and start (Thank Heaven!) and took home.....................

Based on what you said in your original post (quote above) it sounds to me like multiple issues. I agree the starter likely needs contacts, but that's probably due to constant cranking (overworked as a result of other issue(s)). Bad contacts would not explain the trouble code nor would it explain the instances when it would crank but not start. Keep searching for the root problem or you'll likely need new starter contacts again soon . Tim

PS: I agree that igniter or coil is likely the problem here. The worst part about this sort of issue is the fact it's intermittent. You may need to troubleshoot by replacing parts one at a time until you happen upon the solution. Try to find another Previa in the salvage yard and take the distributor, the igniter, the coil, and the ECU..............maybe even the AFM. Chances are the problem is in one of these components.

[Ari]

Hey All,

Good points, on all fronts. Luckily I have a line on a local Previa that matches my own, so I'm not at a loss for parts. I looked the MAF over the other day and it looked just as clean as the relay box next to the battery, as did the ignitor/ignitor coil next to the distributor cap, under a heat/road debris shield. Doesn't mean that they are functioning though...

Any chance that you can send some pictures of the ECU, the ignitor and ignitor coil so I'm clear as to what is what, and where they are located/how to remove/install them? If there are pages in the service manual that are specific to these parts and how to get at them, that would be ideal!

Thanks,
Ari

[djshimon]

goin' to the junk yard! good times to be had!
listen to Tim and you'll be fixed up in no time.
i forgot about the code.

[Ari]

Hey Gang,

HoKay! As promised, I've completed the rest of Tim's instructions.

1. There is fuel under pressure in the system, as checked by cracking the fuel line (thanks for the tip on the easy to access spot!) and fuel did squirt.

2. Jumped the terminals that you recommended and a code 12 came up, which leaves a bunch of potential areas to look at, based on the pictures of Tim's service manual.

Since the Cap, wires and plugs are new and the Coil look to be in good shape, I'm leaning towards the igniter (for no particular reason) so I'm going to go get one if the problem persists after redoing the contacts. I've also done a visual inspection of the Igniter and it's clean and looks to be in good shape.

The problem I have is that redoing the contacts just DON'T MAKE ANY SENSE! The starter is cranking the engine just fine when cold, and I can hear it trying to turn it over when its warm. So why bother redoing them??? My mechanic is CONVINCED that's the problem, but my other guy that I had it on the hoist with said it's working fine. I don't want to waste any (more) money going the wrong direction, but he's German, and stubborn! I also called Bosch just to confirm that it's a 1.6KW starter, and it is, albeit a reman.

Should I skip the contacts entirely and go straight for the igniter, then ECU?

Fun and games!!

Ari


ps - Regarding my post #14, don't worry about it, I found them all...

[timsrv]

Are you saying it cranks slow when warm? If that's the case then check ignition timing to be sure it's not too far advanced. You should also use a DC amp clamp to check starter amps. Then compare to the amps it pulls when cold (should be similar). If the amps are excessively higher when warm I guess it could be the starter, but if it cranks at all it's not the contacts. Maybe there's a short in the windings that only occurs above a certain temp???

The code 12 is a completely different issue all together. Clear the codes and check them again if the problem returns. If the code 12 comes back there won't be any doubt that is your core problem (one of the many things that code indicates). Tim

[Ari]

Hi Tim,

Nope, it cranks hard and fast all the time, no change in cranking when it wont start after being warm, so the issue is not to do with the winding or the timing. I think that the issue revolves around the ECU/igniter/igniter coil, so tomorrow I will be replacing both the igniter and coil to rule them out. That being said, they will be parts from the wrecker, so I hope that they are still good.

If the problem persists after that, I'll do the contacts. If the problem persists after that, then I guess its the ECU.

By the way, the Check Engine Light has not come on since the starter temporarily failed a while back. So the code 12 is a stored code. I will clear it tomorrow after putting in a "new" coil and igniter, then I'll take it for a drive and see how things go.

I will keep y'all posted...

Thanks,
Ari

[timsrv]

I personally haven't previously seen or even heard of these parts failing on a Previa (knock on wood), so I think it's safe to assume the salvage parts will be good. Even if there's a problem, it would almost certainly be a different type problem than the one you're having now. The good news is once you've found and rectified it, it's unlikely you'll ever have that sort of issue again. While you're there I'd also pull the distributor from the parts Previa as it could be the pick-up coil inside of there. Tim

PS: I take part of my statement back, somebody here had a Previa ECU fail (due to corrosion).

[Ari]

Hoo Boy!

I feel like this...

So you can probably guess that the news isn't good.

Earlier today, I thought that I had the problem licked. I'd replaced the Igniter and the Coil with fresh uncorroded junkyard fare. I'd been for a test drive and had no problems with "warm" starting, so feeling hopefully confident, I went for a drive to pick up parts for the front end work. To my total chagrin the van wouldn't start (again!) after I came back to get my parcels, and I sat there for an hour and a quarter before the darn thing would run. And when it did, I used the technique in the owners manual of putting my foot to the floor before starting it.

So I thought that I was back to where I was at before, but this time, after running for about 25 minutes, after stopping and while idling for about 2 minutes, it just flat out stalled!! I was so shocked that I had to just roll it out of the way. I didn't try to start it at all for about 5 minutes, and when I did, it fired right up. It got me home, and that's where its been parked since it stopped.

So now I've got a phantom stop to add to the woes!

So.

Tomorrow I'm off to get the contacts redone after all, as my one mechanic is convinced this will solve all.

I did attempt to clear the codes by removing the 2 15A ECU fuse(s), but I still must check the codes since doing that.

Could it be a fuel pump issue, or as I think you suggested, a problem with a sensor maybe? Perhaps I should go with the distributor, then coil, then ECU, as the service manual lists?

Anyway, back to the drawing board. I'll post again tomorrow after the contacts have been done.

Till then...
Ari

PS - Would the "new" Igniter or the Igniter Coil be responsible for the stalling??