Contour Enthusiasts Group Archives Forums General Troubleshooting Diagnostic testing question...

Right now my car lacks power in the morning when you first start it up for about 20 seconds and then it is fine. There are no CE lights or anything. Is there anything I could find by doing a diagnostic check where I put the jumper in and count the flashes of the CEL? What about at a mechanic shop, would there diagnostic be any more comprehinsive?

Come on guys, nothing??? I don't want to be harsh, but this is the third time in the last month I have posted tech questions and no one seems to have a clue. What's the deal? I know you guys can help me figure this thing out.

How would you know it lacks power in the first 20 seconds?

Do you skip the warm up step and aggressively drive the vehicle right away? (that's very bad and not very bright if you do)

In what way is power lacking?
What was the temperature outside?
ATX or MTX?
How many miles?
What year? (I'd guess 95 since you are describing OBD-I steps???)
What engine?
What have you checked?

The jumper trick will only display codes that have set CELs in the past. If you don't have any CELs, your computer is probably clear of any stored fault codes. Your computer wouldn't tell a mechanic anything if you paid for a diagnostic check, so save your money on that. As far as lacking power for the first 20 seconds, I guess I'd say let it warm up for 20 seconds. (It usually takes at least that long for the idle to drop to normal when it's cold.) If it's sputtering or running rough until it warms up, it could be a number of things. Is this an automatic or stick? How many miles? How old are fuel/air filters and plugs/wires? If you can provide a bit more detail, people will have a better idea on what may be wrong. My first guesses would be air leaks, fuel filter, air filter, plugs, and then wires. Possibly dirty injectors which may be helped by a bottle or 2 of injector cleaner over the next few fill-ups. Hope this helps.

First comment: don't drive your vehicle hard during the first 20 seconds after crank. The engine is not designed for that kind of abuse.

Second comment: Modern vehicles generally play with idle air, injector pulse width, and spark timing for the first few seconds (probably longer for OBD-I) after crank. They do this to ensure good combustion (want an easy start and don't want to stall after all) and to get the catalysts to light off quickly so that emissions will drop quickly to normal levels. Or, to put it another way, the engine is too busy with more important things to provide you with peak performance right from crank.

Third comment: The computer will typically not report any codes for driveability concerns (there are some exceptions). The majority of the effort that goes into the computer is emissions regulation related. The only regulations that relate to performance are those that relate to advertising. BTW, the computer will not clear codes simply because you read the codes. Clearing is a separate procedure (or a fuse if you don't have a scan tool.

If your poor power is accompanied with low idle speed, you may have a sticking Idle Air Control (IAC). Cold weather seems to bring these out. If the IAC is sticking, it may respond to cleaning. You should clean the throttle body and add some injector cleaner to the tank at the same time.

Hers's the 411. The Car has 66K miles, air filter, plugs (plat), fuel filter, fuel pump, &DPFE sensor all changed in last 2-3K miles. 95 GL, 2.5lt v6 engine. Just had the cat recall and they replaced the O2 sensors, no CEL.

Here's what happens. In the morning when the car is cold (weather doesn't seem to factor a difference). You start the car and back out of the driveway. Even if you give it about 20 seconds of warm up, when you press on the accelerator to go, nothing happends. My wife reports that she also hears kind of a "gurgling" noise like air is being blocked. Now last week I went out and started the car 5 minutes before she left for work twice, and each time the problem do not occur. This is great, but whatever is happening should not be , even if we did take it right out of the driveway after starting. At least the problem was not there before the cat recall.

Ok, here's the latest. Cleaned the IAC and had ono appearend effect. When I start the car cold, it takes about 35 seconds for it to drop to 1000 rpm while in Park. When I put it into reverse, the rpms drop immediatly to about 350-400, just enought to keep running but very low. At that time if I wait about 10-15 seconds it will go back up to 1000. I back out of the driveway and put it into Drive. The rpms then drop to about 750-800. I press on the accelerator to go and it starts to act like it might stall but only for a split second, then it proceeds for about 2-3 seconds with poor pull and then it is normal. Any thoguhts guys?

Actually 750-800 is "normal" idle RPMs so I wouldn't be to concerned with that as long as it runs smooth. It is odd that it drops to 400 when you shift to reverse. (???) Some stuff to try:

- Reset the computer by disconnecting the battery for few minutes.
- Check the tranny fluid level with the car running and in park. I'm not sure about the gurgling noise and maybe when you step on the gas the tranny is not grabbing. (Just being safe here)
- If you suspect blocked air flow, open the air box an inch or so and see if that makes a difference. (Just for testing, don't drive around much with unfiltered air getting into the engine.)
- Check again for any vacuum leaks or loose hoses around the air intake.
- Double check that all the plug wires are good and are fully seated on the plugs and the coil pack.
- Test and or replace the IAC. This is an electrically operated valve and may be dead.

Did the car always run like this, or just since the dealer worked on the cats and O2 sensors?

Just since the dealer worked on it. I had to take it back too because I found they put it back together without an EGR gasket and broke my driver's side Tx motor mount. They also claimed that the cat failure couldn't have anything to do with the DPFE sensor going bad (CEL only showed up after cats went bad) which is bull. Anyway, the expirience was so bad I just didn't want them to mess it up any more. I should add that the car desperatly needs the Customer Satisfaction Action of replacing the wiring harness. I suspect that this could be a player, but again, its pretty fishy that the car ran superb before the cats went bad and now everything is going following the "fix".