1989 Toyota Camry and TX emission test....

[daydreamer1252]

Hoping to run across a "trained" automobile tech here that can help....


Took the old girl to the inspection station last week and couldn't pass the NOx portion on the low speed (15 mph) cycle on the dyno. The high speed numbers are within parameters. HC was well below on both cycles. Have gone through the OEM service manual and the EGR valve and controller seem to working as intended.


This vehicle is ONLY operated to pull a trailer to the local HD or Lowes and to pull the boat to the lake on the weekend. Certainly less than 2000 miles a year at the wildest guess.


Runs good and is dependable. 425,000 on the rolling chassis. Not however in a position to put lots of money into it. (been unemployed since Feb.)


Question is this....would applying vacuum to the EGR valve so it would remain open throughout the testing increase the HC numbers and put them out of range? Is there anything else that I should be aware of with regard to the emissions test and this arrangement? After I pass the test I can then make adjustments to return to abnormal as necessary....


Thanks for any and all information....

 

[tx1961whaler]

Re: 1989 Toyota Camry and TX emission test....

I have failed NOx before with my old Isuzu truck. I had to clean out the passages leading to the EGR valve with throttle body cleaner and a big copper wire in order to pass. The EGR valve was OK; the passages were carboned up.

 

[Brewman61]

Re: 1989 Toyota Camry and TX emission test....

Once I had a car fail emmisions test until it was up on the rollers, turned out to be a stuck open thermostat. Coolant never warmed up enough to tell the car the engine was warm, so I think it ran rich and caused high readings. New t stat cured problem.

 

[daydreamer1252]

Re: 1989 Toyota Camry and TX emission test....

tx1961whaler and Brewman61 thanks for the replies....the EGR when vacuum is applied manually operates...the engine idle slows noticibly though no missing or stumbling is present....so there is at least a "pathway" for exhaust gasses to reach the intake manifold though it is possible that the port is partially "plugged"....EGR valve is in a place that is nearly inaccessible and didn't want to remove it if not absolutely necessary.....hence the question of what the effects would be of "turning it on".......Brewman61 the emissions tests for non-OBDII cars in Texas are all conducted on the rollers....unfortunately the thermostat and cooling system seem to be working well and it won't be that easy in this case.....

Unless someone can tell me the probable outcome of my idea it looks like I will leave some more skin under the hood and remove the EGR in the hopes that a partially clogged port can be found....ouch...

Thanks all.....

 

[Brewman61]

Re: 1989 Toyota Camry and TX emission test....

I feel for you. Minnesota abandoned it's emmission control testing after only a few years, as it was not doing anything but causing inconvenience and costing taxpayers money. The found out that the vast majority of cars were in compliance and those that were not had many ways of getting waivers to fixing the problem. Typical "we just gotta do something" action that had absolutely no benefit to air quality. Hopefully you can find the problem and get your car to pass. Kudos to you for keeping a 1989 automobile, especially one with that many miles on it, running!

 

[stackz]

Re: 1989 Toyota Camry and TX emission test....

have you checked for ecu codes? it could be a code that isnt throwing a light giving you grief. If I remember correctly the service connector is in the underhood fuse block. You need to take either a piece of wire or stretch out a paper clip and jump the T1 and E1 terminals. I cant remember if you jump, then turn the key to on...or turn key to on and then jump though lol.

anyway, once jumped you will look at the dash and count the flashes of the check engine light. to read properly, you will count rapid flashes then pause, then rapid flashes as one number (flash flash) pause (flash flash) is code 22...then there will another long pause and more flashes if multiple codes. then it will just keep repeating.

if all you get is the same code then thats all you have. see what codes you get and go from there.

I do know most of the time though people who barely fail can normally just swap out plugs and oil and will pass though, but I would check codes first. high NOx will generally affect your mileage and with gas prices these days, mileage does count for something lol.

 

[daydreamer1252]

Re: 1989 Toyota Camry and TX emission test....

Thanks to all...

I now have an inspection sticker for another year.....don't know which "single" item was the cure but....removed EGR valve and found the hole at the intake manifold virtually blocked....unable to "see" it without a mirror and then was not able to tell much....cleaned out the hole and then had to remove the throttle body and vacuum out the large carbon chunks from the manifold as I didn't think they would make too good a diet for the pistons and valves.....also found vacuum hoses for the vacuum controller (which controls vacuum and timing of that vacuum for the EGR) misrouted....interestingly though it passed last year with the misrouted hoses!!....so not sure which was the real offender.....but on the low speed (15 mph) test that it failed originally max standard 1378 ppm.....1st test measured 2208ppm....now 773. High seed test standard 1258ppm 1st test 1228ppm now 1065....those are NOx numbers....

So thanks again for the input and attention....yes it does take a little more to keep an old one on the road but beats payments on something newer....

 

[woosterken]

Re: 1989 Toyota Camry and TX emission test....

glad you got her fixed?? what would happen if you run a bottle of sea foam through her once in a while?

ken