Welcome to the DoItYourself Forums!

To post questions, help other DIYers and reduce advertising (like the one on your left), join our DIY community. It's free!

Rough Idle

gian45man's Avatar
Visiting Guest

Posts: n/a

05-17-04, 12:44 PM   #1  
Rough Idle

I have a 91' Infiniti Q45. Lately my car has been running poorly. Here are the symptoms:

1) Rough idle

2) Black Smoke coming from the exhaust

3) I noticed a hard to describe odor coming from underneath the car, smells like exhaust (catalytic converter?)

4) Poor fuel mileage

5) Lacks power.

I ran diagnostics using the onboard computer and it flashed a 34 code which the book says points to the "Detonation Circuit". Based on what the technical manual says, there are a few most likely culprits:

A) Fuel injectors
B) Spark Plugs
C) Fuel Pump
D) EGR Valve

Does anyone have any ideas?

Sponsored Links
davo's Avatar

Join Date: Apr 2002
Posts: 2,417

05-17-04, 02:21 PM   #2  
I would remove the egr and see if it's stuck open.Also check your air filter and look for any hoses that may have come off or be cracked and leaking.

Desi501's Avatar

Join Date: Oct 2003
Posts: 2,207

05-17-04, 05:16 PM   #3  
A scanner would be very helpful here so you could study the data and look for something out of parameter. You could have a Mass air flow problem, O/2 sensor, fuel pressure regulator or even EGR. There are many things that can give you a rich idle.

Search this Thread