How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Dr. Hamman Your Own Question
Dr. Hamman
Dr. Hamman, Chevy Technician
Category: Chevy
Satisfied Customers: 6286
Experience:  30 Years Experience repairing, customizing, and building chevys.
Type Your Chevy Question Here...
Dr. Hamman is online now
A new question is answered every 9 seconds

I have a '94 Chevy lumina. It'll start but won't idle. Just

Customer Question

I have a '94 Chevy lumina. It'll start but won't idle. Just replaced the fuel filter, the fuel pump, and put in a pcv. Plugs don't show any sign of blow back. I'm stumped.
JA: Does the engine turn over? How old is the battery?
Customer: It's starts great. But the second I take my foot of the gas it dies. It's got a good battery
JA: Are you hoping to fix this yourself?
Customer: Well I was.. Depends on how much time it'll take to fix it
JA: Is there anything else important you think the Mechanic should know about your Chevy lumina?
Customer: I just learned that it hasn't had a pcv for the past 2 years. There was a lot of oil in the air filter.
JA: OK. Got it. I'm sending you to a secure page on JustAnswer so you can place the $5 fully-refundable deposit now. While you're filling out that form, I'll tell the Mechanic about your situation and then connect you two.
Submitted: 4 months ago.
Category: Chevy
Expert:  Dr. Hamman replied 4 months ago.

Which engine does it have, and have you checked it for vacuum leaks.

Customer: replied 4 months ago.
It's the 3.1 multi port. It does act like it's not getting air, maybe..? Which how I learned about it not having a pcv for the past few years.. I am not sure where to begin checking for vacuum leaks.
Expert:  Dr. Hamman replied 4 months ago.

The best way to check for vacuum leaks is to get a can of WD40 and spray all around the intake manifold, and vacuum lines. If you hit a vacuum leak it will speed up for a second or two. That allows you to find almost impossible to locate vacuum leaks. If that doesnt solve the problem, I would suspect the IAC. It controls the idle speed via the ECM. Think of it as a robotically controlled idle speed system. The IAC might be bad, it is a fairly common failure. There is a reset procedure for the IAC. You remove the ECM fuse for a few minutes, reinstall it and fire up the engine, immediately placing it in gear with your foot firmly on the brake. This makes the computer re calibrate the idle speed. Sometimes it takes a few tries. If it has a vacuum leak, or the IAC is bad it wont re calibrate. One last thing is if you have a vacuum leak the IAC cant do it's job, that makes it critical to search for vacuum leaks first.

Customer: replied 4 months ago.
Thank you! I'll check for vacuum leaks and go from there.
Expert:  Dr. Hamman replied 4 months ago.

Okay, let me know if you have any more questions, I will be happy to help.