94 Escort LX 1.9 Manual Weird idle and highway driving

[chwilkin]

I will do the best I can to be as descriptive as I can be, though this is not going to be easy. It is hard to describe what is going on, and I'm thinking that I may have more than one problem, but here goes.

While idling my car will drop to 800rpm or lower, sometimes shutting off the car. Mostly, though, it will rev back up (on its own) to around 2000 and then drop again. It keeps going up and down and up and down. This does not happen all the time, and seems to happen less frequently with a warm engine, though that is not always the case.

While on the highway it feels (I'm using this as a descriptor, not necessarily saying this is the problem) like maybe a cylinder is not firing and the engine has to pull the cylinder along. Problem seems to occur mostly at 70 mph, and I think is causing the clutch to wear out prematurely. It makes the car shake and goes away mostly if I increase the speed I am attempting to go. Then it will go away only to occur rarely, but then I'm traveling at 80mph, and still that's no guarantee it will work properly.

And the final issue is when starting out in 1ast gear the car will sometimes get stuck in what I can only assume is the same issue I described above. Acceleration is almost nothing and only dropping the clutch and revving it to around 5000-8000RPM seems to fix it. Then i grab back on to 1st gear and have normal acceleration.

Known issue: EGR valve (or something like that) that "helps emissions" was bad when I bought it, and didn't think it could be causing this issue. If it is, I will replace it of course.

Any help is appreciated.

[mightymoose_22]

It is probably a combination of problems.

Start with the basics and we'll have a better idea of where to look... are the plugs and wires new, recently replaced, or due to be changed? Are they connected tightly at the plug and at the coil pack? Are the plugs gapped correctly?

Does the car idle normally when parked?

Is the transmission leaking or low on fluid?

Is this the original clutch? If so, how many miles on the car? It is likely due...

Considering a possible clutch issue, it is possible that you have fluid leaking onto the clutch, which means your acceleration problem might be due to slipping.

Remove the inspection cover at the bottom of the transmission and check out the condition of the flywheel... see if it is wet in there. I had this problem once and it was due to the main seal leaking onto the clutch.

As for the rpm fluctuation, more info will be needed. If plugs and wwires check out, investigate the fuel pump.

Provide more info after your preliminaries and we can look further in to it.

[chwilkin]

Plugs are new and gapped properly. Wires are not, though I suppose I should replace them. All connections have been checked, and rechecked.

Car idles the same regardless, though since yesterday I now have a break in my exhaust line and am seeing a bit better performance, though I can still hear it sputter when it does its highway trick.

Transmission not leaking or low on fluid.

Clutch was replaced one month ago. Brand new. Could be fluid leaking onto the clutch, but it feels a bit weird for that.

Haven’t checked the fuel pump yet.

Will check wires, fuel pump and get the exhaust line fixed, and get back to ya.

[Davescort97]

I'd go along with mightymoose22. If your car has over 50,000 miles it needs new plug wires. Bad wires will send a signal to the PCM and the ECU making the idle oscillate. Get OEM Autolite or Motorcraft wires. The ones you get at Advance or Autozone aren't that good. Bad wires will short out when you need power the most----Under a load!

[chwilkin]

Oh it's over 50k.

It's got 140k on it right now. I love these cars. Had two of them in the last 4 years, and they're so reliable except for the weird problems. And even those are few and far between.

I will replace the spark plug wires and see where we're at. Any other suggestions are fo course always appreciated.