hey guys, i think my egr valve or solenoid is bad on my 90. i was wondering how you can check to see if it is bad before takeing off the plenum. also i couldnt find the selonoid i thought it was next to the distributor anyone know.
thanks for any help, mike

 

On my '88 the Sol is on a metal bracket bolted to the rear T-stat housing bolt.

You can apply engine vacuum directly to the EGR valve at idle to see if it moves.

You can jumper the Gry wire to the EGR Sol to ground and see if the valve closes at idle.

 

Applying vaccum to an L98 egr valve won't work it is operated with exaust gas to enable it to open .
I for get what it is called check with the local parts store they can explain it to you.

 

This info's from my 86 but may prove useful
http://members.shaw.ca/agent86/EGR%20System.pdf

 

Hogwash! The vacuum hoses and the solenoid are there for decoration? Or maybe they're a decoy for your parts picker. Read your HELMS!!!. Although SOME parts people can be very knowledgeable and helpful, they are not generally considered THE authority on how things work.


canon1414,
You are concerned that there is something wrong with your EGR valve or solenoid. Are you afraid it isn't opening? Or that it isn't closing?

RACE ON!!!

 

i have been getting a code 44 since i bought the car last summer and someone on here told me it could be the erg valve i have both the chiltens and the helms books and i read how to test it but i did'nt know where the egr selenoid is and how to check the egr valve with the plenum still on.
thanks mike

 

Hook up a hand vacuum pump and see if it lifts the diaphram.

Do this with engine off. If the engine is running, exhaust backpressure will bleed off the vacuum.

If you don't have enough backpressure, it'll hang open when you shut the car off, possibly throw a code.

You probably just aren't getting vacuum to it.

 

In my year, a code 44 indicates a lean exhaust. In any case, follow the trouble shooting charts in your Helms, for code 44. An EGR problem could be part of, or all of, the cause for the code. If so the Helms should direct you to make tests on the EGR system. Otherwise, the Helms should explain the operation of the EGR system and locate the parts for you. My Helms has a small sub-section, just for the EGR.

RACE ON!!!

 

To see the egr diaphram move, you'll need one of those $1 pen mirrors to stick under there, and a flashlight. They have em at the counter at pepboys,autozone,etc

 

You may want to check your EGR switch also, but I think thats code 32.
Its located at the top of the EGR tube thats runs from your exhaust manifold to the intake manifold.

 

Doubt the valve has anything to do with the code - a vacuum leak could, so check the lines using the vacuum diagram on the radiator.

If you haven't, make sure the O2 sensor wire is in good shape, especially if you've all ready replaced the O2.

A 44 usually means air is getting into the exhaust stream from some other source and no matter how much the ECM tries to compensate for it - it can't. Have you had the headers off? If so, suspect an exhaust leak.

Clamp the air pump lines to the headers - if the Code goes away, remove the check valves and make sure that you can only blow air through them in the direction of the headers. If good, the switching valve may be bad or the ECM isn't switching from headers to CAT after warm up. Check the latter by removing the hose to the CAT and verifying that air is flowing through it once the temp gage shows 160 or so.

Plugged up or weak injectors can cause a lean condition. Ohm them out and cold. Should be 15 to 17 ohms across the terminals with little variance between any of them.

Check fuel pressure - 40 to 42psi key on - 38 to 40 psi when it's running. If the pressure is too low, replace the filter first.

Finally, make sure it's not leaking coolant into the exhaust - pull the #7 plug (since that seems to be where most of the early aluminum head motors fail) and check for rust on the threads - turn the engine over until #7 is a TDC and see if any coolant comes out of the hole - check compression hot and cold.

 

Hey guys i am home this week and started working on the car and i
I couldnt find the egr valve. i have a 90. anyone know where it is.
thanks, mike

 

The EGR valve is under the plenum, right on top of the intake manifold.