My first engine problem
 

This morning and then again this afternoon, I started car and it felt rough idle, almost quitting. This is first time I have noticed as much as a wimper. I am not a mechanic but can turn a wrench and change/ clean parts.

Where do I start?

Note after I took off car runs fine. Took about two or so seconds under way to straighten up. From reading maybe the MAF. I have a 2000 base with 60,000 and a upgraded IMS, new plugs, new heater hoses all in last 6,000 miles.

If you have a durametric, check for codes, also check for a vacumm leak.

Start by seeing if any codes are pending in OBDII. If it's running that bad some should be pending even though no CEL.

Otherwise, it's pretty much anyone's guess and you could spend a lot of time and $ chasing unnecessary parts...

Could be MAF (which you can try cleaning or disconnecting/running in safe mode), might be a coil pack (6k should have shaken any bad install out before now but look at them to see if any might be cracked), maybe AOS starting to fail but usually it'll just go w/ lots of smoke (pull off j-tube at TB and look for any oil pooling), vacuum leak big enough would trigger CEL before rough running would be noticed.

Good luck :)

I've had the same issue for a while now and nothing shows on the ODBII. Vacuum leak test at the local mechanic is on the list of things to do but they run $300-$350 and no guarantees that'll tell me what's going on. I hate these types of issues.:ah:

Can a vacuum leak only effect cold start up. No smoke at all and on MAF what are the systems that I should watch for. Just took her out and ran perfect on start up and had a Chevy Truck roll some smoke trying to race me, took care of him in a second or two. It was funny to watch him slip into his seat.

A vacuum leak might be worse on startup but should continue to affect the engine after warm up.

I hate to say this, but unless you want to start replacing several $200+ parts one at a time, the best thing to do is to wait and see if it gets worse and then you might be able to isolate the exact cause.

Well it has to wait for a short time. We had our 6year old pom fall of the bed. She had back surgery and now is three hours away having physical therapy. Plus we are headed on a trip to Hawaii then a week in San Francisco. So I am busy and cash flow short until July any way. Just don't want to damage it any more. I can drive the new Ram that we bought last week end but gas is expensive it that thing.

Take off the oil filler cap and tell me your car doesn't run rough.

I will try that tomorrow. I have done that before and it was similar but not as rough. So I see your going with a possible vacuum leak but why would it get better in a few seconds.

Good point. I'm assuming you have an e-throttle, but if you have a mechanical throttle,try cleaning the idle control valve.

I guess I would start with the easy stuff. Clean the throttle body, MAF and then if that doesn't help, try troubleshooting the MAF, but as someone else said, don't just spend $300 for a new MAF unless you are pretty sure thats the problem.

How do I know if I have an e-throttle or not.

If you have a throttle cable, its not e-gas.

Many auto part places will read your codes for free, that's probably a good place to start.

What year and mileage is your car? I had some rough idle symptoms recently and it was two coil packs that went bad. Easy fix!

if it was a coil pack or ignition you would get a flashing CEL immediately

Just a thought, could bad gas cause this. When I was in Columbus with the dog is filled up at United Dairy Farmers store and the smell from the tank and car was very strong and funny. My wife even ask if had spilled some on me. We could smell it from inside car going down the road. I figured one tank of cheap gas being ran out at 70mph that day would not hurt me. Was I wrong. Going to fill up this morning at normal station and put in super premium $4.29 a gallon.:eek:

If you smell gas, then a gas leak could be the cause of the rough running. A leak could prevent fuel pressure from building up quickly enough.

Update- This morning it was bad and had the flashing CEL but nothing the rest of the day. Filled up at normal station with high test within minutes of start up. CEL has not come back on and car is running fine. Will take out in AM and see if it was bad gas - fingers crossed.

Why not just get the codes read? Then you won't have to guess...

Right now it is a timing issue. The local dealer is two weeks out and the only indy that I know is on vacation. I am going to local auto parts to see if they can read codes, not sure without cel on will there be codes?

Buying a code reader is not the most expensive thing you'll ever do for the P-car. And I always found it helpful on other cars, neighbors cars, etc.