Real Fiero Tech

what do you think is causing my check engine light to come on.
I can drive the car all day long at 60mph for any number of miles with no problems, ,but once I hit 65mph the check engine light comes on. The car still runs fine and if you turn it off the then back on the light is off until I hit 65 again. Any ideas? it's a 88 V-6

What codes did you pull from the computer? What rpm range does the light come on at?

need a little more detail. could be the EGR, or could be a faulty signal from speed sensor to ecm

manual or automatic?

It was a code 32 and I think it's a vacuum leak where I used a piece of rubber tubing to connect the line to the egr valve. How do you tell if it's a leak or a bad EGR solenoid?

Rule out the vacuum leak by spraying WD40 at the suspected leak area while the car is running. If there is a leak, the idle should increase when it sucks in the WD40. Carb cleaner will also work, but be careful with the fumes. Also tuolene (carb cleaner) can be damaging to rubber and plastics.

ghetto-fabulous way to check the EGR valve without a vacuum pump is to disconnect the EGR vac. line, reach under the EGR mushroom and push the diaphram up, then with the other hand put your thumb over the vacuum nipple. When you release the diaphram, it should more-or-less stay put, and not (for example) go back to rest with a whistling noise. :thumbleft:

If the egr valve holds vacuum, check your vacuum line for cracks, and make sure it fits tightly on the nipples.

Thanks for the replies….and I admit that my question was a test ……… I really do have this problem and I really don't know shit about car maintenance or repairs.

Word of advice: Keep the social commentary in RFT Vs. World and not in Tech or Will will get medieval on your thread.

In other news:

Also, you can do the same check on the solenoid side of the hose to see if the hose leaks (assuming the diaphram doesn't show evidence of a leak).

You can also hook up a vacuum guage and see if there's vacuum at idle.

I'll confess here that I'm not 100% sure of the conditions required for the solenoid to be open (have vacuum at the EGR valve). You'll have to wait until I have a chance to look it up at home, or for someone else to chime in.

I BELIEVE (but am not sure) that the solenoid should be CLOSED (no vacuum) at idle, and open at cruise (which is difficult to test in the garage).

If you've got a vac pump and guage, you could always turn the motor off, and apply vacuum to the manifold side of the solenoid and see if it holds it.

from what I remember the solenoid is closed all times except at cruise low throttle above 3000rpm

the solenoid also has a sensor built in that can fail.

the real question is do you want to fix it properly? or just fix it so you don't get a code anymore.

nutswinging V8Archie fool wrote:Thanks for the replies….and I admit that my question was a test ………

:flipa:

I have the same problem, and I just posted in the other forum that I tested the valve, but I guess I missed the part where you're supposed to see if it holds in place....so I'll test it again......tomorrow.

It's there for a reason, I want to fix it right.

Starlite528
i'm sorry that i'm new here, so i haven't seen everything that you have tried.

but i'm pretty good at figureing out code 32 problems.

if you would like to retell your story, i would give you what ever feed back i can.

Well, here's what I found when I took the intake plenum off. Apparently, my father, the previous owner of the car, had a shop do some work on the car, and this was the result. What a mess. I cleaned it up and put a proper gasket in place. As for sealing the tube, using jb-weld now instead of that mess the other guy left behind.

Wow, the gasket was causing a leak, that sucks. you can probably braze the tube back onto the flange.

That pic was taken right after I took the plenum off. Notice the gasket almost perfectly blocks the tube.