98F-150 v6 4.2L
It starts just fine.After I have its started the motor revs up and down 4-5 times then it sooths out just a little..
Let me start by saying I replaced both my 02 sensers,Throttle position sensor,Air Idle control valve,fuel filter,and Plugs and wires and it still wont run smooth.the rough idle is noticable in park, worse in drive when waiting at a light thats when it idle down and I have to put it in neutral to keep it from stalling.I had it put on a machine and no codes came up at all.Looks like I will have to bring it in to the shop but would like a little advice from anyone that thinks might be my problem..
2006-09-24 10:04:11 · 6 answers · asked by Anonymous in Cars & Transportation ➔ Maintenance & Repairs
pcv hose was checked and is ok.
2006-09-24 10:11:03 · update #1
If you checked for codes and none were present, then the next stop for diagnostics will be for someone to run a "MOVIE" during the failure.
Sometimes there are failures caused by a component not monitored by the computer system, or a component is just inside the parameters that would trigger a code.
The tech will need to drive the pick-up with his scanner connected and when the engine begins to act up, he can trigger a "movie" which records the engine parameters for all the components monitored for 15 seconds before and 15 seconds after the trigger event.
Now he can compare all the readings and when he finds the one that just doesn't "fit" with all the others, he can begin to focus on it, and remedy the failure.
Unless you own one of these pieces of equipment, you will have to take it to a repair facility or the dealer.
You can expect to pay about one hour's worth of shop time for the diagnostics. The repair will be another matter, and will be based on the time required for the repair, and the parts necessary to correct the failure.
Good Luck
2006-09-24 10:31:27 · answer #1 · answered by Ironhand 6 · 0⤊ 0⤋
I'm sorry to hear that you just "threw" a lot of EXPENSIVE parts at it, WITHOUT FIXING THE PROBLEM!!! Firstly, the symptom you describe sounds like you have a vacuum leak. If it is high on mileage, you probably need new intake gaskets. Are there any DTCs (diagnostic trouble codes)? If so, was it a P0171 or P0174? Those are the lean code DTCs typically for vacuum leaks. How is the IMRC operation? If IMRC (intake manifold runner control) isn't functioning properly, the symptoms you describe can also occur.
2006-09-24 10:11:00 · answer #2 · answered by Anonymous · 1⤊ 0⤋
Vacuum leak. No big deal. Unless your engine is missing while driving, then you need a timing adjustment or your idle speed is too low. Minor adjustments or replace the vacuum hose. Its still kind of new so its nothing serious.
2006-09-24 10:21:13 · answer #3 · answered by diamond_joe1979 3 · 0⤊ 0⤋
With it at idle, listen for a higher pitched sucking noise.
More than likely a vacuum line\hose came off the intake manifold "T" connector.
2006-09-24 10:23:10 · answer #4 · answered by Mr. KnowItAll 7 · 0⤊ 0⤋
sure , water ,air and gasoline are sturdy places to start up. maximum persons do not change those filters ofter sufficient besides. Get some gasline antifreeze or ask your elements shop for some sturdy chemical compounds to get rid of any water. The gasoline we are getting now must be no longer the suitable, some has water "outfitted it". when you've done those issues and if it really is nevertheless performing up, examine for vacum leaks. anybody of those many, many lines lower than the hood or lower than the sprint ought to reason the topic matters your are describing.
2016-11-23 19:31:00 · answer #5 · answered by ? 3 · 0⤊ 0⤋
The pcv (valve) hose is broken
2006-09-24 10:06:39 · answer #6 · answered by kayef57 5 · 0⤊ 0⤋