howdo

Trying to diagnose an egr code of 32. I read in some archived posts about checking/replacing the EGR temp. switch. It sounds like the switch should be on top of the egr tube. I can't find the temp switch. I even went to the dealer and they said there is no egr temp. switch for '91 corvette. I don't get it. If there is no EGR temp switch to let the computer know if there is EGR flow, what sensor tells the computer there is an EGR malfunction?

Thanks

:confused:

CorvetteZ51Racer

I honestly don't know if there is an EGR temp switch on the '91s or not, but if there is, it should be mounted on the passenger side of the EGR valve. Look in between the runners on the passenger side of the motor at the EGR valve (which is mounted on the base under the plenum), and you should see a single wire going into the side of the valve, where the temp switch screws into the EGR valve....again, assuming there is a temp switch on the '91s.

VAHROOM

As far as I know, 89 was the last year of the temp switch. Are you getting a code 32 after cruise or all the time? My 90 used to get a 32 after cruise due to a leaky diaphram in the EGR. I just pumped down the vaccuum in the valve and let it set for a few minutes. It bled off in about 20 seconds. I replaced the valve and no more 32. Good luck


[Modified by VAHROOM, 10:24 PM 4/20/2004]

howdo

Vahroom, thanks for the response.
I was getting a code 32 during cruise. I checked the solonoid and it seems ok. I tested the EGR valve with a vacuum pump and it does not hold vacuum (the vacuum immediately bleeds off). I bought the car about 4 weeks ago, and it had the code 32 then. About 2 weeks ago, all of a sudden the car started to idle very rough and stall. I had to keep my foot on the gas at a stoplights or it would stall. I checked the fuel pressure and and it was fine (I was thinking it was maybe a fuel pump or clogged filter). I was going to start to dig into other possible causes (not sure exactly what), but I read that sometimes a sticking EGR valve could cause stalling, so I though I would replace the valve since it won't hold vacuum anyways. Do you think I'm on the right track to fix the rough idle?

65Z01

I too can't believe there is an EGR witout a sensor but since the valve isn't holding vacuum it's likely the the vacuum diaphram is leaking causing the idle problem.

When you replace the EGR Valve check for the temp sensor on the valve; if it isn't on the tube just before the tube goes into the intake base.

VAHROOM

If the vacuum leak is severe enough it could be the cause of the rough idle. Plug the source and see if it smoothes out. There may be other issues though. Give it a tune-up. I am just guessing but it may need other maintenance items also. Just plugs, rotor, cap and check the wires.

On another note Mr. EGR is cheap and easy to change.Take a small wire brush gently inside the EGR passages to break gunk free and then get out the shop vac so you don't have to revisit.

Let us know what the resolution is for this ends up to be. It may help others in the future..