Power loss - I'm going nuts!

[Aarontsiawd]

Hi,
I recently started having a power loss problem with my 1993 Talon Tsi AWD. Every so often (and getting more frequent), the engine will suddenly lose a LOT of power and have very little throttle response. Downshifting to a lower gear doesn't make much of a difference. The engine doesn't make any weird noises or blow any smoke, but it feels as though it's starving for fuel or the timing is getting pulled way back (this is just a guess since I have never experienced either of these in the past). This power loss doesn't seem to happen at any particular time - it has occured when accelerating onto the highway, or just cruising along steady at 60 MPH in 5th with no load. Just as suddenly, the power loss stops and the car starts running great, as it usually does. Some background: the engine is pretty stock with just a K&B and EBC. I always run premium gas. The car has never given me any real problems in the past and has always run great and strong even with 122k miles. I haven't changed the fuel filter in many years and I thought that might be it, but why would it be so intermittant? The computer is original, but it makes no clicking noises or smell. Any suggestions would be appreciated. Thanks.

 

[marcmsj]

It could be a number of things but start with the easiest... When's the last time you did a tune up? It could be something as simple as bad plugs and/or wires.

 

[Locke]

Any CEL? Pull the codes to check for stored codes, may be a flaky sensor or intermittently bad connection. If the problem becomes more frequent, try disconnecting the down pipe from the catalytic converter and seeing if that solves it or not.

 

[Aarontsiawd]

I forgot to mention that it does flash a CEL when the power loss occurs. It goes out as soon as the engine starts running back to normal. I plan on doing a full tune-up and fuel filter change this weekend. Thanks again for the responses and any other suggestions.

 

[Defiant]

Step One: read the CELs stored in the ECU.

 

[Aarontsiawd]

I changed the fuel filter (took about 30 minutes) and put on new plug wires. The Taylor 8mm wires had some light burn marks. The car now seems to run great. I can only guess that the wires were 'leaking' which led the knock sensor to pull the timing back. Thanks for the replies.

 

[1gcrazy]

Hey man, I'm having a very similar problem except my CEL doesn't flash at all...
Let me know if you find anything out. I'm clueless...

 

[mhuffman]

I have a problem similar. during cruising with a fixed throttle setting, i will loose significant power. when i roll into the gas, i have very little acceleration. Then suddenly the cars power comes back, as if there was nothing wrong.

 

[cturok7]

Hey man, I'm having a very similar problem except my CEL doesn't flash at all...
Let me know if you find anything out. I'm clueless...

Does your check engine light ever come on?
I mean it's a good question.

 

[mhuffman]

No CEL. I've considered the electrical wiring for the fuel and ignition, as well as sensors. maybe even the ECU.

 

[rush2252]

No CEL. I've considered the electrical wiring for the fuel and ignition, as well as sensors. maybe even the ECU.

First thing in a 1g check the ECU it takes 20 min to remove check reinstall. 2nd Always check for boost leaks in a turbo charged car. A boost leak will make one run like your describing. Broken motor mounts etc can cause the motor to shift and make intercooler hoses come loose you might have a leak and not know it

 

[mhuffman]

First thing in a 1g check the ECU it takes 20 min to remove check reinstall. 2nd Always check for boost leaks in a turbo charged car. A boost leak will make one run like your describing. Broken motor mounts etc can cause the motor to shift and make intercooler hoses come loose you might have a leak and not know it

good advice, but i have filled motor mounts, no boost leaks, and i recently checked the ecu. thats not to say the ecu might be going bad.

 

[mhuffman]

i put my cat in and switched to a softer bov spring and retuned and the problem has subsided. could be coincidence, but who knows. i also giggled all my wiring around to check for bad connections.