1994 Q with Occasional Check Engine Light

[Q45inNH]

Hello. I purchased a 1994 Q45 with only 88k miles from a friend of mine at work. It was his father's, then his. He said it the only issue was that it occasionally did not shift out of 1st. The price was right. I've had the car for 5k miles and the transmission did not shift out of 1st just twice. A concern, but manageable. The CEL light then started coming on after driving on the back roads. I drive 48 miles on the hight way to work and back each day and the CEL does not come on. Only on the back roads, does the light come on - after a few miles. Turn the engine off and the light will stay off for a few miles, but then comes on. Because for the last 15k miles, regular 87 octane gas was used, I tried the Chevron textron, Guaranteed to Pass, and Lucas fuel system cleaner, think that the system needed a good cleaning. No luck

This past week, the "transmission malfunction" indicator came on at start-up, then went off after a few seconds. I took the car to AAMCO ( 100 yeards from home) and they said the only stored code was for the EGR valve. I reviewed this site - lots of good info - and had them clean the EGR valve & sensor, as well as the 3 transmission sensor connectos. I picked the car up and the CEL came on after 3-4 back road miles.

Any ideas? One problem or two?

[elwesso]

Well you have two different issues in my opinion. IF the CEL is coming on while cruising and the car seems to run good (no hiccups or misfiring), then it's likely to do with the EGR or the o2 sensors. The AT issue is something else.

Check the ECU codes, using this procedure. Post up what code it is:

http://www.nicoclub.com/archives/infini ... codes.html

For the transmission, do the self diagnosis outlined in the service manual...

Go to www.nicoclub.com/FSM, go to the Q45 section, 1994, AT.pdf, and start reading on page AT-41. Post the results. Be sure the car is warmed up when you do this, if it's not warmed it may not do the self diagnosis properly.

[Q45inNH]

The CEL had gave a 32 code. EGR valve, sensor, or tube? Has never gone on with the engine reving over 2k.

However, the transmission did not have a stored code. Thinking the problem is way too intermittent.

[Infinitiguy19]

Are you in New Hampshire? If so where abouts? I don't mind meeting up with you and helping you out. I have a ECUtalk cable and I can use a laptop to connect to your car.

[Q45inNH]

Yes I'm in NH. Exeter (office), Concord (home). I am out of town for business until the 9th. Are you close to either?

[Infinitiguy19]

PM Sent!

[elwesso]

If you're getting an EGR code first thing I'd do is take the EGR and TB off and clean out the passage that goes between the EGR valve and the intake. My guess is it's epically full of carbon that it's 100% blocked. All you'll need is a new EGR and TB gasket, and the time to do this should only be about 1-2 hours. You'll need lots of brake parts cleaner.

[2brokey]

I am dreading doing that EGR job myself... it's going to make a lovely charcoal-flavored mess. There is also that little temp sensor for the EGR system but I somehow doubt that is bad. The vacuum portion of the EGR can be checked with a Mighty Vac to see if it actuates or if it is stuck.