Rough idle, need some help please
Senior Member
Joined: Mar 2009
Posts: 1,062
Likes: 50
Lean conditions are the result of insufficient exhaust has detection by o2 sensor. Yes, air leak after MAF can be the cause but it's usually the simple stuff that gets overlooked. Start with your spark plugs. When was the last time they were changed? If you don't know then they probably need changing especially with 320k on the clock. Coils may also be weak. Any idea what your fuel trim levels are at?
Senior Member
Joined: Mar 2009
Posts: 1,062
Likes: 50
Lean conditions are the result of insufficient exhaust has detection by o2 sensor. Yes, air leak after MAF can be the cause but it's usually the simple stuff that gets overlooked. Start with your spark plugs. When was the last time they were changed? If you don't know then they probably need changing especially with 320k on the clock. Coils may also be weak. Any idea what your fuel trim levels are at?
Thread Starter
Junior Member
Joined: Apr 2014
Posts: 7
Likes: 0
From: Portland, Or
Clean your throttle body guys! Go to Advanced get some MAF Cleaner and Deep Creep for that throttle body! Mine did the same and would even die if you played with the pedal at low rpm and rough idle. Had oil caked on the bottom of it and around the rim! Runs like a champ now!
Also try 5w30 thats what i'm running since im over 200k now. Does it have the Gott's mod? Could give that a whirl and see if itll make the MAF give you more gas to not be on lean side.
Also try 5w30 thats what i'm running since im over 200k now. Does it have the Gott's mod? Could give that a whirl and see if itll make the MAF give you more gas to not be on lean side.
Thread Starter
Junior Member
Joined: Apr 2014
Posts: 7
Likes: 0
From: Portland, Or
I think cleaning the TB is just general good maintenance but if you're getting lean codes, you don't want to increase airflow... in fact lean conditions can be caused by increasing air flow with CAI's or even the Gott's mod... i would check the intake (starting at the filter) for leaks... if you don't get a seal on the air filter, it can suck too much air and throw lean codes
Thread Starter
Junior Member
Joined: Apr 2014
Posts: 7
Likes: 0
From: Portland, Or
Lean conditions are the result of insufficient exhaust has detection by o2 sensor. Yes, air leak after MAF can be the cause but it's usually the simple stuff that gets overlooked. Start with your spark plugs. When was the last time they were changed? If you don't know then they probably need changing especially with 320k on the clock. Coils may also be weak. Any idea what your fuel trim levels are at?
This seemed to happen suddenly tho. I came across a thread on the FPDM, Fuel Pump Driver Module. There were many horror stories and pics of trashed modules. These are located on a frame rail above the spare tire. Great! Of course in my case the socket that goes on the end of the crank-stick is missing so I can't drop the spare! Les Schwab doesn't have a "key" or any of the other parts stores I checked. Dealer only I believe. I even checked with a few neighbors. One guy had an '02 and he had the crank-stick that fit right in to the pocket, no socket required.
Does this sound like FPR? Fuel Pressue Regulator? (if the FPDM is in good shape)
Good point. I have no idea when the last tune-up was but she's been running great for the past year I've been driving it. This seemed to happen suddenly tho. I came across a thread on the FPDM, Fuel Pump Driver Module. There were many horror stories and pics of trashed modules. These are located on a frame rail above the spare tire. Great! Of course in my case the socket that goes on the end of the crank-stick is missing so I can't drop the spare! Les Schwab doesn't have a "key" or any of the other parts stores I checked. Dealer only I believe. I even checked with a few neighbors. One guy had an '02 and he had the crank-stick that fit right in to the pocket, no socket required. Does this sound like FPR? Fuel Pressue Regulator? (if the FPDM is in good shape)
With your milage I would absolutely do a full ignition system tuneup. You won't regret the peace of mind, and the elimination of countless variables with future and current trouble code diagnosis..
Go to the junkyard if you need to complete your OEM road hazard tool kit.
Member
Joined: Jun 2014
Posts: 59
Likes: 6
From: Md
I think cleaning the TB is just general good maintenance but if you're getting lean codes, you don't want to increase airflow... in fact lean conditions can be caused by increasing air flow with CAI's or even the Gott's mod... i would check the intake (starting at the filter) for leaks... if you don't get a seal on the air filter, it can suck too much air and throw lean codes