Rough idle & periodic misfire, any sufggestions?

[darklamb]

Hey All,

I 'm having a bit of trouble with my 1998 Ford Escort. Here's a bit of history of the problem.
1) The first indications were that I was losing power during acceleration and experiencing surges. Otherwise, everything was running smoothly.

2) The next progression was , when I started the engine cold it idled a bit rougher than normal but not too bad. It began to cutout and I had a cylinder misfire. The check engine light came on, so I took it to the Ford dealership so they could check it out. They changed the spark plugs and wires, and said it was all good.

3) It seemed to be running okay when I got it back, but it still ran a bit rough and 2 days later I had another cylinder misfire. If I drove a bit so the engine was warm, stopped to get gas or run a short errand, then restarted the car, the engine idled very rough and began to cut out. I took it back to the Ford dealership. They had it 2 days and were unable to tell me what the problem was or offer a solution. They indicated to me that the check engine light came on because of the misfires (seemed to indicate both misfires were on cylinder 4) but they didn't offer any suggestion or solution to the problem. They didn't seem to give it much effort or thought.

4) Now I've got the car back because they weren't accomplishing anything with it and I couldn't afford to rent a car for any longer waiting for them to reverse their rectal-cranial inversion. The car now idles extremely rough when started, even when cold, but when gas is applied seems to smooth out. There is also a pulsing hiss coming from the engine compartment.

Anybody have any suggestions, cause I havn't a clue.

Thanks in advance,

Donovan

[mechy1barry]

the hiss is probably the intake,is the car only used for short journeys?,if so it could be gum up,first thing to try is an injection cleaner,and a good make of oil additive to clear valve stems and lifters, and to take the car on a run of 10 miles or so,redlining the revs in 2nd 3rd as long as you can,(be carefull!)if this does not clear it,mail me.

[darklamb]

Thanks, for the suggestion. Actually that's the first thing I thought of. It didn't seem to have an appreciable effect.

The noticeable hiss is a recent developement. I wonder if my problem might be related to a vacuum leak somewhere. Is this a fault that would be easily identified by the computer. When I suggested this possibility to the service tech, he dismissed it out of hand. Can anyone suggest trouble shooting tips to help identify probable locations for a leak.

The fuel filter is brand new and I'm getting fuel so I don't think it's the fuel pump.

Are there any other possibilities for a solution?

Thanks,

Donovan

[mitchell1204]

go to Auto Zone or O'Reilly's auto parts if there's one near you. they will come out in the parking lot and pull the trouble codes for free. definately have a sensor problem. my educated guess would be the throttle position sensor or the air bypass valve sensor is bad. also escorts are bad about the EGR valve clogging up with carbon. this can be fixed simply by removing and cleaning.

[darklamb]

Thanks, for the suggestions I'll check them out and let you all know how it goes.

Cheers,

Donovan

[need4speed420]

i know exactly whats wrong with it. you have a vacum leak going into the throttle body, i had one also, it costs about $15 to fix it......... theres a hose going into the throttle body, it is probably what is leaking the hissing sound is air being ucked into the throttle body....... get some propane, and let it leak out of a hose, put the hose around the throttle body and see if the idleing get better in omeplaces

[darklamb]

Well, I finally got an answer to the problem. I took the car to another mechanic. He did a compression test on the cylinders, paying particular attention to the one that kept misfiring. While the problem was occuring there was almost no compression in that cylinder. We've decided that the valve in cylinder 4 was going wonky. We're going to have to remove the head, rework the valves, replace all the gaskets and at 97,000 miles the timing belt is due to be replaced anyway.

Cheers,

Donovan

[herefordman]

The steel valve seat insert has loosened in the aluminum head, your one of the lucky ones, and appear to have caught it before it cracks, falls out, and smashes the piston top and head all to crap, this is really common with this engine, Ford should be ashamed of themselves to have such a highly repeatable problem.

[marussell]

I think I have this same problem with my girlfriends car, it's also a 97. Do you need to replace the head or can you install the revised valve guides listed in the TSB?

[12Ounce]

BURNED BY THE CHRONIC VALVE INSERT PROBLEM!

1996 Tracer (build date 4/96) 2.0L, 145 kmiles. Daughter's car. Well maintained. Little warning. Did get misfire code on cylinder #4 ... similar to Darklamb's (above). The engine suddenly started up noisy and quickly locked-up solid. Had to be towed home.

At this point, I've removed the cyl head. Head and piston have been pecked-up pretty good in #4 cyl. Intake valve insert totally chewed up into small pieces. Head may not be reusable, I'll go by machine shop tomorrow and determine if it is or not.

Cyl #1, #2 , and #3 are almost perfect: no carbon build-up, just soot, on piston crowns ... no detectable wear on cyl walls. Synthetic motor oil. But piston #4 is obviously broken, and the piston crown stays at top of cylinder ... I have not yet opened up the short block. Just hope the crank and block are reusable.

(The really scary part is; I have another daughter who also has a '96/'97 Tracer!)

EDIT UPDATE: After examining, the guy at Dover Cylinder Head Repair says the head is repairable ... and that he's seen many of them ... always seems to be cyl #4.

So now for the short block inspection .....

[steelsoldiers]

Crap, 1st post here, and it looks like it's a bad one. My wife's 1999 Escort made a lot of noise and wouldn't start for her the other morning. When it finally started it sounded awful!! Me and my brother did some exploring on saturday. The timing belt was fine, but when we tried to roll the engine over by hand with a ratchet, it wouldn't turn all the way over. We pulled the plugs and found the electrode of the #4 plug smashed flat against the tip. Crap! I stuck a magnet in there to see if I could pull any pieces of anything out, nothing.

This reall ticks me off. Only 127, 000 miles on the thing and it takes a dump in the driveway with no warning!!

I guess we'll pull the head off next to see if we can salvage the engine. Any more tips from guys who have been trhough this?

Thanks for any help!
Chris

[12Ounce]

Sorry you may have joined the "busted valve insert gang" ... but you're lucky there was no tow charge.

Just today I've gotten the block to the machine shop and found its rebuildable ... in fact the bore be may just honed and stay "standard" saving me many bucks not buying oversize pistons, etc. A testimonial for synthetic oil! The head is also in the shop.

I expect this is going to cost under $1000 and that includes new hoses, belts, mounts, etc ... but I may be getting too much Sun!

We'll all find slightly different conditions inside the engine. In my case, the piston had broken in-rwo just at the oil ring and the upper portion of the piston stayed at top of travel. The bottom protion, the "skirt" was sideways trapping the bent rod in place. I had to drill a hole in the piston upper, and install a 1/4" lag bolt to remove it from cylinder. Then there was access to reach down with long nose pliers and break the skirt into small, extractable pieces.

The engine is normally only removable, according to the "book", attached with the tranny. But if you strip the engine down to the block ... there's no problem coming out and up. Four 10 mm bolts, a couple of 4' lengths of chain, a 8' length of deck board across the fenders ... and you have a rig that will allow a couple of weaklings to lift the block and crank.

Had a bit of trouble separating the flywheel from the torque converter ... tooks lots of Rust-Buster!

If you've never use it, I advise you to look your engine up under the maintenance pages at AutoZone.com.

[12Ounce]

An update on engine "overhaul" .... necessary because of inlet valve insert coming loose:

The block wasn't so "rebuildable" after all!

Cylinder #4 required an insert because of wall damage caused by wrist pin. I don't like the thought of cylinder inserts, but it may be the best in this case. (The cost keeps stacking up!) Now I'm waiting for four .020" oversized pistons to be shipped in. Next week sometime.

The cylinder head has been picked up from shop. Looks good. $135. They assure me all valve inserts are now "well-cinched" and will be no more problem. (Too bad Uncle Henry couldn't have done this initially.)

BTW, (I forgot to mention this before) as the intake runner was being removed from engine, I noticed that the gaskets on both sides had imperfections (gaps in the moulded seal) that looked as though they've been there forever. I'm sure these things have been leaking ... though not enough to give us CEL's.

Just remember this if you have intake leaks that you cannot find!!!

[dlbdata]

On the dropped valve insert problem, what are your opinions on whether it is common enough that it would be worth having the valve inserts replaced in advance? My 95 1.9 pings a fair amount, I've started using 89/91 octane, has 105k miles on it. Wonder if a job to clean the carbon out would be worthwhile and fix the insert problem at the same time?

[12Ounce]

I think it's an idea with merit ... but not on a 1.9. As far as I know, this problem only belongs to the 2.0 single-cam engines. ????