I have been running the EGR all the time for 2 years.
My van runs fine cold and hot. Winter and summer.
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I have been running the EGR all the time for 2 years.
My van runs fine cold and hot. Winter and summer.
Hi all,
Recently my van was running poorly. I replaced the plugs, wires, rotor, and distributor cap which made the van run great. I was going to replace the TPS but never got to it.
Soon after, I took it in to get smogged and it passed- with the exception of the timing. They said it was off. Hmmm. Ok.
So I took it to a service place by my house. They readjusted it (and said it was a PITA and that I got off easy with their original quote of $100) and I drove back to smog.
Smog guy passed it and I took it home. Problem is, it doesn't run as good as it did before the timing adjustment. When its cold it runs really bad- no power, lag, hesitiation, etc. But when its warm, not great either. I feel like it runs through the gears really fast and it has very little pick up off the line. I have to hammer the throttle to get it to move and there is little to no snap in the acceleration.
So, is this likely an issue with the timing? Maybe the guys didnt set it right?
What about the TPS? Would this make a difference if I replaced it? Does setting the timing with a bad one require a resetting of timing with a new one?
And finally, can this be done easily at home? Not sure I want to pay another $100 or more if I can do it in a few hours at home (timing that is).
Thanks for any and all help,
Dennis
The base timing will not be correct if the TPS is faulty. I recently just went threw something similar. Mine is 1989
I cannot figure out how you passed smog if the timing was incorrect since my smog test was an automatic failure for being 15 degrees too advanced and it too ran great with the timing advanced however it would not pass smog because of the timing being advanced which produced High N0x gases. The Van failed on incorrect timing and High N0x. Hydrocarbons were actually really good
In order to pass smog they had to retard the timing to 8 degrees BTDC which is in spec, however my Van ran like how you described your van, low power, except mine ran like crap with the timing set correctly in my case.
In order for my Van to run well the timing has to be advanced 15 degrees and so I suspect there is something with the distributor, but since the workaround has been advancing the timing I will stick with it as I am getting no detonation , no pinging and no noises. When its time for smog again, I just retard the timing again
My van passed all of the emissions related stuff but failed due to the timing being off. I assume the timing was off since I had changed the distributor cap and rotor. Then the guys in the shop timed it with a faulty TPS and that led to the poor performance?Quote:
Originally Posted by JPERL
JPERL, do you think if I replace the TPS and have the timing adjusted, the van will run well and be within spec to pass smog? Is it difficult to do the timing myself? Thanks for the help!
If you did not remove the distributor itself or loosen the mounting bolt to rotate it, the timing was not impacted by replacing the cap and rotor wires, etc. Highly unlikely.
A bad TPS will cause the following
Hesitation or poor acceleration
Bad MPG
Ignition timing being off
Surging or hunting idle (sometimes stalls) Surging is where the idle rises and falls repeatedly and will stall when the idle falls to low before surging upwards again
Quick deceleration can cause stalling usually a red flag that something is up with the TPS because it is slow to respond to the fact that the throttle has closed and the fuel cut signal to the PCM is late
the TPS is not that expensive but is absolutely crucial that it is adjusted correctly otherwise an incorrectly adjusted brand new TPS will cause the same symptoms as an old bad TPS. I would replace the TPS if the history is unknown being that the TPS is one of those items commonly overlooked. Many times unnecessary ignition components are replaced to remedy a TPS issue on an old vehicle.
Get the TPS addressed first because a bad TPS creates domino effect symptoms such as bad timing, poor acceleration, hesitation etc..
Timing is not hard to set. What makes it hard is locating the timing marks especially if the timing cover is caked in oil and grime.
You need a timing light (cheap one about 25 bucks)
a wrench to loosen the distributor to turn it to adjust timing
a jumper wire to short terminals T and E1
Thanks! Gonna replace the TPS and go from there.
I will post results when I get it done.
After moving with my van from Manitoba to California I am almost ready to brave the smog test. I have held off on getting it done while figuring out an idle problem that would have guaranteed failure. Now that I've finally got her idling for cold starts there seems to be nothing else major that would effect it. Since we do not have smog tests in Manitoba I am unsure of what other components I should test before bothering to bring it in. What maintenance/ repairs/ component testing can anyone recommend for helping my chances of passing?
can't help with CA smog specifically as i'm in oregon. but i have seen a few youtube videos that have very good tips and tricks for getting temporary really clean emissions readings by tweaking a few things and using some fuel additives.
The good thing about smog in CA (I am from Texas originally, where they don't have smog tests) is that you can go and get a test done. If you don't pass a certain requirement, you can fix it, go back to where you smogged it and they will retest it free of charge (within a certain amount of time). You only have to pay for the initial test. Just a thought.
Also if you are worried about it passing, some places you can have them do a "pre-test" to get readings. Basically they don't transmit the findings or log you into a database. I have done this in the past when I was pretty sure a car wouldn't pass, but didn't want the "gross emitter" tag attached to the record until I could fix it.
Vans generally pass smog more often than they fail. Owning many of these over the last 30 years, The most I have had to replace to get a passed inspection, was the catalyst and the EGR modulator. But that was in only 2 out of 5 Vans. If the vehicle was reasonably maintained you should pass relatively easy.
2 important Items
Make sure your Van idles at the correct RPM. For example, If it idles at 1K rpm it will not pass the visual inspection, regardless of whether it is putting out emissions within range.
Ignition Timing is very important. If the Timing is too advanced that will raise your NoX emissions
What is the TPS?
Thanks for the help!
This is the Throttle Position Sensor located on the back side of the Throttle Body. Throttle Body is the device attached on the passenger side to the intake manifold and on the drivers side to the black flexible rubber hose connected to the Mass Air Sensor and that to the Air Filter. Beck-Arnley (Italy) is the best replacement as this is NLA Toyota stock. Tim has posted several threads and videos on how to clean Throttle Body and then mate and set up the TPS to the Throttle body. Search!
Quick Update. So one year later, it’s back to the smog shop. Once again, passes smog but the timing failed. Van still running poorly and I just want to get it registered. I decided to finally replace the TPS. Was actually pretty easy, I did it without fully removing the throttle body-but of course didn’t get to clean it either. But having two kids and a busy life makes for quick repairs. Anyway, van was running better now that the TPS was replaced. Took it to a shop where the guy was familiar with the vans to get it timed. I got a good price since I took out the passenger seat and access panel for him. He said the timing was retarded way too much. Previous guys probably didn’t know what they were doing and didn’t jump the plug when setting it. He set it to spec and WOW! I forgot that the van ever ran this great. Smooth starts and no lag on acceleration- even when cold. Runs through the gears and shifts when it should. So much power and speed that wasn’t there before. I’m in love all over again. I’ve had this van for a while and don’t really drive it much, I think it’s time to do some more work on it and get it on some adventures.
So if your van needs timing, make sure the TPS is good and take it somewhere that knows what they’re doing (if u can’t do it yourself).
Thanks.
Sooo.... What's the deal with buying a vehicle out of state and bringing it to California?
Reg'ing does not seem to be a problem, but what about smog stuff? If it was not a car originally destined for the Golden State, does it need all the bits and pieces and pass the tests?
What of it?
Thanks!
RG
Rg,
IF it was built for Calif. specs it should be good. The state of tune will define whether it passes the state testing or not. There are some threads about meeting CA emissions standards. Good thing is if the vehicle you are buying fails I believe the vehicle can be turned to a junkyard for $1500.00 from the state of CA. My comments based on other posts on this site about CA vehicles. Good luck!
Hey Tim long time.
does your statement to jump the connector apply to 1984 as well? I just had my smog done and the tech showed me that in his book it does not say to do that. Nor on the sticker. It says 8 BTDC with vacuum hoses removed from distributor and sealed. So it was 20 degrees advanced doing it his way with out the plug jumped and I had to pay him extra to retard it to 8. Although if I recall where I used to take it they did it with it jumped And I haven’t touched the distributor in the past 2 years. Now the acceleration is anemic and it dies at idle until it warms up.
Quote:
Originally Posted by timsrv
Hi theojo :), Yes, it's been a long time :yes: Glad you found your way back.......even if only for a short while. The advice to which you refer was given to the owner of an 87 van, but I should have stated it only applies to 86 - 89 vans. Jumping the "Check Engine Connector" disables the Electronic Timing Advance (which is necessary to properly set timing on vehicles so equipped). Since 84 - 85 vans used the older style vacuum advance, jumping the connector is not necessary.
As you correctly pointed out, you would pull the vacuum line to the diaphragm on the distributor and plug it.........then set and/or check the timing (with that line plugged). It's also recommended to verify engine is idling @ 950 RPM or below while checking/setting the timing. To verify the advance is working, after the timing is set/locked @8° BTDC, reconnect the vacuum line and check again to verify it jumps up to ~ 20° BTDC. Tim
Yeah I should lurk on here at least more often and help out the newbies as you do. It’s just that my van so rarely needs help that I have no need.
Younare of course correct as I read in the FSM after my initial post. Perhaps the fellow failed to disconnect the vacuum tubes in his initial test since he got exactly 20 and it had been running fine. I’ll check that.
thanks
I think I am having a similar smog / timing issue. Van has been running fine. Smog place failed the van due to the timing being at TDC instead of the van spec of 12 degrees. The actual emissions numbers were good, I have a new cat from 6 or so months ago. I paid them to adjust the timing and redo the smog test and it passed. But now i can hear the engine making a raquet/pinging? underneah me in every gear. Should I just pay someone to put it back to TDC for the next two years? I don't have a timing light.
I also have a new TPS from about 6 months ago, don't think its related because the van has been running fine.
LBT - You should just go buy a timing light, they have become quite inexpensive in the last 10 years.
Sadly, things like setting timing, adjusting carbs or doing house plumbing with copper, are all "things of the past" and many of the current practitioners are not well versed in the "old ways".
Keep in mind there have been a few people that have had harmonic balancers that have rotated which moves the timing mark from it's correct location. If the inspections are looking at correct timing based purely on that mark than your timing may in fact have been correct even though the tech and your timing mark say it isn't.
man, i feel sorry for you cali guys...damn van passes emissions and they still mess with you...dont you have to remove the passenger side engine access panel to even shoot a timing gun on the harmonic balancer?!?
The first time they failed me was because the hose coming off the air boot that originally went to the A/C idle up diapgragm was plugged with a bolt. My van didn't have A/C when I bought nor does it now. The smog guy said it was EGR on the printout. Saw that after he told me it failed of course. When I said I didnt think that hose was emissions repated he started talking about how the state is cracking down and giving citations. I wasnt mad at the guy. Just the whole situation. The second time I went back is when he said the timing was off. So I had to drive there 3 times total, polluting all the more, take off work, pay more, be punished for not being able to afford a car from 2015. I wish I hadn't forgot about that damn hose at least.Quote:
Originally Posted by boogieman
Its not like I WANT to pollute or think its all a sham, but it starts to feel like a slap in the face over and over after a while. By the way, my hydrocarbon numbers went up and almost made ir fail smog the second time after they fussed with the timing.:doh:
Ok, after calls to half a dozen smog places and getting turned down, with excuses from pre 90’ cars are too tough to get an accurate rpm reading, to people knowing these vans or rather how to access the motor and denying it out right I found someone local.
Took my van in today, and getting everything dialed in went through the test, passed the sniffer, rolling test, got to evap test and failed. Tech explained it was losing pressure somewhere between filler neck of gas tank and pipe to charcoal canister.
Looked (searched, but no success) in forum any ideas what is causing van to fail? Tech says it is either leak at filler neck, somewhere on tank or the rubber hose from tank to charcoal canister.
thanks
Glad I don't live in Cali.
Considering that we never cared about evap systems till '95 it seems bizarre that they even bother looking at that side of things.
How the heck do they even test that system?
All that said, there isn't much to check.
If it were me, I would pull the top of the air filter box and get in behind it with a mirror and light and see if you can get a look at the topside of the canister.
Granted you don't live in the rust belt so may not apply, but from underneath mine looked brand new, topside where the alum cap attaches to the steel body was an entirely different story
Worth taking a look.
BB
I been trying to get my van legal to pass smog but seem to be having a hard time. ive done a very basic tune up on the van ie plugs, air filter, fuel filter, fresh fluids. And tried to smog but failed horribly. Nox was way to high as well as the HC fluctuates anywhere from 15-2000. tech said timing and idle is off. Well i got the timing set to 12° but its till idles in about the 800-900 range. It all spits put the exhaust. After doing so the nox has come down to acceptable ranges and passes at idle and 15mph but is still to high at 25mph.
I dont feel like its the convertor due to the fact servers recorders show its only a few years old. I feel like it has something to do with either egr or the o2 sensor but im kinda stumped.
Ive tried blowing out the egr and it seems clear though i did get alot of dust out of one line. Also I found the bvsv has broken off and has been by passed.
My next step is to replace the o2 sensor I guess and try running some injector cleaner though the engine to see if that helps. But idk where to go from there if it doesn’t
Can you post a pic of the numbers on the smog sheet?
The catalytic converters on these vans are set way back. If the replacement cat isn't OEM quality it won't heat up properly, and won't last. I run fiberglass header wrap from the manifold collector all the way to the cat. This helps keep the cat hot, and working properly. I originally did this for smog reasons and it helped tremendously.
Realized, I never updated this post. I pulled an evap canister from a van at PnP and removed all the hard & soft lines from fuel filler to tank and then from tank to canister. Pressure tested hard lines, and replaced all the soft lines. Passed no problems.Quote:
Originally Posted by bikerjosh
@Sperrunner , i have had cars that were tough to pass before and might have some ideas. Feel free to PM me. Learned some tricks from Corvette forums.
I dont have the original sheets on me but at 25mpg my nox was about 3800. After a tune up and proper timing i got the nox to about 1500 at 25 mpg. Which is the speed im worried about rn because at 15mpg im now in acceptable ranges.Quote:
Originally Posted by VanCo
As for the cat it looks after market judging by it being welded in. And its sits above 23rd the way back in the exhaust system.
I passed the evap test. But im failing due to nox. And I think it had something to do with the engine not running perfectly. I can’t actually get the engine to idle at 750 with 12° of timing.it idles like 850. Its also popping out the exhaust.Quote:
Originally Posted by bikerjosh
If your HC and CO are good at both 15 and 25 then it would seem the engine is running efficient.
NOx emissions are effected by increased cylinder temperatures. Exhaust gas recirculation (EGR) helps by reducing cylinder temps, as does proper ignition timing. Another obvious way to reduce inside cylinder temperatures is to keep the engine cool at the proper operating temperature.
In order to reduce emissions even further (once it is established that the engine is running properly) a catalytic converter is used. When the cat is heated, the various metals and precious metals react with harmful emissions and convert them into less harmful emissions. A properly working and heated cat can clean up the emissions of even a poorly running engine. This is why (for emissions reasons) it is important to make the engine run perfect before condemning the cat.
If your engine temp, EGR, and timing are good, I would suspect the cat. If its legal in CA I would try the header wrap on the exhaust prior to getting a new cat. Just my two cents.
Im not 100% sure if my egr is good. Ive blow through it and it seems to flow ok. Though alot of debris came from one line. Also the bvsv is snapped off and bypassed.Quote:
Originally Posted by VanCo
My first corse of action was gunna be trying to replace the egr system, o2 sensor and see if running some seafoam though will help clean all the carbon deposits on the pistons and valves
Yeah, fix the EGR system. Sounds like it isn't functioning. I like seafoam, works great. Replacing the O2 won't hurt, but if your HC, and CO are good I would guess it's not needed (replacing them periodically is good insurance anyhow). I used a narrowband O2 gauge to monitor mine, cheap and shows you how fast it's responding.
Hc is fine at 15 and 25 but it goes crazy at idle from 15 - 2000 hc.Quote:
Originally Posted by VanCo
Nox is ok at idle and 15mph but still high at 25mph
I know you've covered some of these, I'm just listing everything I can think of.
Idle pop, and random high idle HC:
Cap, rotor, wires, timing
Vacuum leak
Computer doesn't know it's idling, check TPS
Slow O2
Bad carbon build up, slow drip the seafoam into a vacuum line like an IV
High NOx at speed:
Timing too advanced
EGR
Catalytic converter
You may also want to make sure your timing marks are correct on your balancer.
Getting into trouble with CA smog here on my 1984 Toyota Van.
It didn't pass. It barely failed on NO, and it was smoking. It also has smelled weird for a while.
It appears to be burning oil. The smog guys said I should do a compression test and a cylinder leakdown test. The valve guides might be messed up.
Other people have said the rings might be worn out. Of course I want to fix all that stuff, but unfortunately I don't have much time left before the certification needs to be renewed.
I guess what is happening is oil is leaking into the exhaust.
I put some 91 in the engine and the Guaranteed to Pass stuff. I'm going to drive it on the highway a lot and try to burn through the whole tank and see if that cleans it up.
I also picked up the Lucas Fuel System Cleaner but I haven't put that in yet.
I also had someone tell me you could cut the cat off and clean it, but other people have told me that won't work, it's not like, a reusable component. I can weld so if it's actually something to try I could.
Of course I want to take the whole engine apart and fix the leak, but I need to get this to pass with the time I have left.
Anyone have some input? Are all those weird cleaning additives like Guaranteed to Pass and Lucas BS?
Or does anyone want to buy this thing? Because if I can't fix this I might have to junk it.
run 20-50W. I have been using this in my high mileage vans for 30 years. What is the mileage? If your engine runs rough or stalls I would do a compression check. If you have readings below 100PSI in any cylinder that cylinder is effectively dead and not burning the fuel mixture and that being dumped into the exhaust will raise your NOX emissions. Start with Cylinder 4. My 3Y failed the emissions like yours is doing (back in 1993)and I had 90PSI in cylinder 4. Got to the point I had to feather the throttle to keep it running
I’m in CA with an 84. Mine doesn’t smoke but runs very rich. You can smell it at idle. Yet it passed 2 years ago with a CARB legal Catalytic Convertor that I got from Rock Auto for around $200. Also the rich smell went away. Until I changed it back to the old CC 3 days later knowing it would be destroyed by the unburned hydrocarbons. I’m pretty sure my original injectors need cleaning. Poor gas mileage.
some places check the smoke more than others. My guy revs it and then runs around to the back to check. So try 50 weight For the smoke and a new cat for the Nox.
edit. Unfortunately the only CARB cat they have now is $436 at RockAuto
Oh man everything has been so hectic, it was actually the HC it failed on and I wrote that wrong a couple posts back.
Ok I switched it to 20W-50. I've been trying to burn through the whole tank of 91 before I go back.
I might also clean the MAF sensor before I go back.