Help. Power loss when accelerating. Feels like A/T slips, but not really.

[riddin dirty]

1998 Contour 2.0 with A/T and 70K miles.

New MAF and Coil.

Power loss under moderate to hard acceleration. Transmission revs up with no go.

Under easy throttle the transmission shifts really good no hesitation that I can tell.

Hook up timing light and even with new coil the light is is not a constant like I expected.

New to Ford's and the Contour so I am not sure.

Help anyone?

 

[projectSHO89]

Transmission revs up with no go.

How does a transmission rev up?

 

[riddin dirty]

It's strange. Took to dealer for diagnostic check. Told it was the cat and it would be $2000. Took it home and busted out cat. Still got the same problem. I am puzzled.

Transmission shifts fine under low load..no heavy foot. Apply the heavy foot and the car stops pulling as hard and finally the engine revs like it is slipping. This happens in any gear at any speed. Take off from a dead stop with lots of gas and you get slip. Ease back on the throttle the car pulls and shifts hard in the next gear.

Try to kick in the passing gear running 55 mph. Transmission shifts down, revs go up and you go no where. Ease back on the throttle and car picks up speed again.

PCM? Shift sensor? I am lost.

Recap on history: 70K miles. New MAF, cleaned out cat, new plugs, wires, even replaced coil pack (but took back after no improvement). NO CEL....at the moment.

 

[beefgravy]

It's strange. Took to dealer for diagnostic check. Told it was the cat and it would be $2000. Took it home and busted out cat. Still got the same problem. I am puzzled.

Transmission shifts fine under low load..no heavy foot. Apply the heavy foot and the car stops pulling as hard and finally the engine revs like it is slipping. This happens in any gear at any speed. Take off from a dead stop with lots of gas and you get slip. Ease back on the throttle the car pulls and shifts hard in the next gear.

Try to kick in the passing gear running 55 mph. Transmission shifts down, revs go up and you go no where. Ease back on the throttle and car picks up speed again.

PCM? Shift sensor? I am lost.

Recap on history: 70K miles. New MAF, cleaned out cat, new plugs, wires, even replaced coil pack (but took back after no improvement). NO CEL....at the moment.

This could be a fouled out plug or broken wire. I would pull the plugs and check the gap and inspect all the wires. It would sound and act normal until a lot of gas was pushed into it and the fouled plug won't ignite it fast enough causing a slug or decrease in power.

I know you just did a plug change over, but if they are gapped wrong or they sold you faulty wires/plugs you wont know until you pull it.

Beef

 

[riddin dirty]

Good call. I re-checked the gaps. No problems. The wires are presumed good.

I used a timing light to check the spark for each wire before trying a new coil, plugs and wires. The spark is inconsisent. This lead me to try the coil. I noticed absolutely no difference after installing a new coil. Changed out the plugs and wires and still no change. The inconsistent spark leads to think it is the PCM. The transmission slippage may be another symptom of the of the PCM or a result of the inconsistent spark.

When I checked the spark I expected a consistent flash with it accelerating as the rpms were increased. I got most of the that but then there was an occasional no spark that made me think the coil was bad. No I am thinking PCM, but how does that tie into the transmission issue???

 

[riddin dirty]

Ok. Here is the update. It is fixed. Runs like good again. No trans issues, power loss, etc. All is good.

Turns out that the shade tree (not me I promise) who replaced the fuel pump a month ago pinch the fuel line leading to the filter when he re-installed the tank. Can you believe it?? That was it!!

I looked for the fuel filter as a last ditch attempt to fix the car and found the pinch fuel line. Basically, the car (my mother-in-law's...you know got keep em happy) was running on fumes and screwed up the PCM, then tranmission, etc.

The only bummer is that I wasted a perfectly good CAT in the process of trying the fix the car. I suppose I can thank the dealer's bum diagnostic check for that. Oh well, all's well that end's well.