Mechanics have me confused!!

[angelm231]

Ok, I'm not only confused but absolutely furious! I went to a reputable auto repair shop last week to have the cover for my exhaust tightened. When they were done the CE light was on. They did a quick diagnostics and said the gas cap was loose. The light went out but came back on by the time I got home. Couldn't take it back in for a week since I only have 1 day a week off. Took it to them yesterday, they did a diagnostics, can't tell you the part they replaced but it was $260. (It was like a plug located at the front of the engine, one screw) When I went to leave the CE light came back on again so they did another diagnostics. Apparently they read it wrong the first time and put the wrong part in. They told me it was some sort of a solenoid that needed to be replaced, on top of the engine, and that it was another $75. I told them I didn't have anymore money and they basically pushed me out the door (yes, they put the old part back in!). Now, this is my question. One guy told me the solenoid that needed to be changed basically controlled or sensed air flow and that the only problem I might see is that I might lose power once in a while. Another guy, their mechanic, said it also determined the oil flow? Eventually, the second mechanic threw up his hands and walked away. Then the first guy reitterated that my truck was fine to drive and that I would just lose power sometimes. I'm to take a long trip next weekend to be with my kids but can't afford the trip AND the solenoid. Does anyone know which part I'm talking about and is it safe to drive my truck until I can afford to fix it? The truck runs great, but once in a while I do feel I'm losing power, but not much. HELP???? PLEASE???

[vancouverbc]

did they charge you for the $260 part? these things are hard to diagnose. replacing parts doesnt usually fix the problem because it is oftening the wirng or connections.

[carmo]

Without knowing the actual code that caused the check engine light or knowing exactly what system on the truck your talking about, it's really hard to help. A knock sensor won't cause a check engine light but will cause you to produce less power. Evap sys. issues will not cause driveablity issues. EGR sys. issues can go either way. Stuck closed EGR valve or just totaly inop. won't hurt anything. Stuck open and the truck idles like crap but still driveable for long distance. Oil pressure sending unit would just leak or cause an erroneous light if it malfunctions. Mass Air Flow sensor on the other hand directly affects air fuel ratios which if too far one way or the other your talking burning aloth of gas and just running like crap or worse yet, not delivering enough gas and causing internal engine damage. Oxygen sensors also deal with air fuel ratios but if they fail the computer has a "fail safe" mixture ratio preprogramed that will allow the engine to operate safely. You should be able to get away with a road trip on a bad O2 sensor however, of course the disclaimer, I wouldn't recomend it. I hope this helps and good luck

[pm_page6776]

Sounds like your mechanics are chasing two different issues. First your check engine light is most likely a code for an intake timing control solenoid. Chances are they replaced the intake timing sensor (the plug) thinking it would correct the issue. This code can be caused by several things. The sensors go out often as do the solenoids, but this code can also be caused by engine sludge or low oil level. I would check your oil level first. If you post the code number it would help. Second, the mechanic likely wants to replace your mass air flow sensor. A bad mass airflow sensor would cause a hesitation but may not be your primary concern. Are you worried about the lack of power or your check engine light? An intake timing control solenoid code means your camshaft on one bank is not advancing correctly. You will not have to worry about it if you cannot afford to fix it right now. You should not even feel any difference in drivability. If anything, you may get slightly less gas mileage on your trip.

[nothing]

I was also thinking EGR solenoid/valve. I'd go back to "mechanics" and ask for the diagnostic results which I think you paid for, right? Retrieve codes from results, post here or take results to another mechanic and asking how much they would charge to get that done.