Loss of Power / Engine Light

[turbobrick]

My wife just called me and told me about a problem on her 95 Escort LX (manual transmission)
On the freeway, it suddenly lost the power and quickly decelerate (engine did not stop, though) and Engine Check light came on, started rumbling and unstable feeling on the handle. She was going to get out of the freeway to stop engine, but the engine came back after a little bit and engine check light turned off.

Again, this morning, same thing happened, only this time the light stayed on. The power came back so that it started accelerate again normally, but light stayed on. Also, when I was waiting for the light in idling, it stalled.

Any ideas? A vacuum hose would only stall the engine but not cut out on the freeway?!?
Thanks for any suggestions - i will have to get the engine code downloaded

UPDATE - drove today to AAMCO to get the codes checked out. On the way the engine lost again power and engine light came on, but disappeared later again. No white smoke from exhaust (even at high rpm)
OK, here are the check engine light codes:
157 - Mass air flow signal too low
181 - cruise rich limit bank 1 still lean
186 - injector pulse with high or MAF too low

All three codes sound related to me - let me know if i am wrong and it looks like the MAF sensor is either bad or the connector is loose

how do i check the MAF?

thanks again for any feedback

[Intuit]

Check coolant color. Run a compression leak-down test on it. My guess is the head may be cracked. What do codes read ? 'Fuel at adaptive limits' or something similar ?

Also, after so much time, it's common for the intake and exhaust manifold fasteners to back-off. The former may cause a large enough vacuum leak for such a severe problem to occur.

Unrelated, MAF and ACT/IAF should be cleaned along with normal maintenance of filter/sponge clean/replace but wouldn't cause those symptoms.

[Davescort97]

I would go along with intuit, but we need that CEL code.

[FordMan59]

Try to get us some trouble codes. Maybe it'll help us with some ideas.

[Intuit]

When you update, make a new post because we aren't notified when you edit an existing post.

A problem in the ignition system (plug wires or spark plug gap) can cause similar problems; though usually missing as opposed to simple power loss. The reason I didn't mention that before is due to the fact that I've never heard of, or experienced that triggering a light.

A mechanical combustion issue probably wouldn't result in a MAF code. BUT, keep in mind that it is possible to have more than one issue. Most codes will be silently recorded in the PCM and won't trigger a light. It may help to confirm which of the codes, if not all of them, triggers a light.

Regarding the MAF (and the ACT/IAF right next to it,) try cleaning it before replacing it. Local autoparts store will carry MAF cleaner, sometimes called electrical cleaner; or electrical contact cleaner.

The white smoke at high RPM could possibly be oil getting past the valve seals.

[five-oh-H.O.]

Originally Posted by Intuit

When you update, make a new post because we aren't notified when you edit an existing post.

A problem in the ignition system (plug wires or spark plug gap) can cause similar problems; though usually missing as opposed to simple power loss. The reason I didn't mention that before is due to the fact that I've never heard of, or experienced that triggering a light.

A mechanical combustion issue probably wouldn't result in a MAF code. BUT, keep in mind that it is possible to have more than one issue. Most codes will be silently recorded in the PCM and won't trigger a light. It may help to confirm which of the codes, if not all of them, triggers a light.

Regarding the MAF (and the ACT/IAF right next to it,) try cleaning it before replacing it. Local autoparts store will carry MAF cleaner, sometimes called electrical cleaner; or electrical contact cleaner.

The white smoke at high RPM could possibly be oil getting past the valve seals.

I totally agree with what intuit is saying. Here also is a quote I posted in another forum:

the problem may be with the mass air sensor on the intake throttle body. i had a similar problem, so I opened up the sensor module (after buying the necessary tamper-proof bits) and found that there was a build-up of corrosion on the thin wire thread-like element. Using an electrical parts/sensor cleaning spray, I cleaned up the sensor and the issue was solved. If there is any problems with this sensor element, it can cause any number of issues with air/fuel intake.

[mightymoose_22]

Keep it simple to start... check/clean/replace the air filter. If all is well, a good cleaning of the MAF may help.