Any mechanics in the house?

My car is having an intermittent but persistent problem, and my mechanic is pretty much scratching his head over it by now ($1100 later, that is). The car is a 1991 Plymouth Sundance 5-speed, 4 cylinder (I believe the engine is a 2.0 or 2.2 litre - I would have to check on that), with 140 000 kms on it. The car is fuel injected.

The problem is that the car hesitates, bucks (and no, it isn’t my shifting :)), pulls/strains to keep power, loses power then surges, idles rough occasionally, and gets darned close to stalling out while idling (this isn’t very frequent, however).

What we’ve done so far (from deciphering my mechanic’s writing):
timing belt
rebuilt head (?)
gasket set
head bolts
rotor
plugs
wires
(this one I can’t figure out, so I’ll just type what he’s written) “r&r cyl head and change timing belt”
map sensor
pick up coil
I’ve been using an STP fuel injector cleaner with every other tank of gas as well.

The problem went away for about 6 months after the last fix, but it seems to be creeping back again now.

Anybody got an idea what’s wrong with this car that is otherwise running quite well? Anybody got any guesses at what to try next? Any help would be much appreciated.

How about the Lambda sensor ?

It sounds like it could possibly be a fuel/air starving problem. The easiest things to check (if they haven’t already and you just neglected to mention)
Air Filter
Fuel Filter
Fuel Pump
Air-Flow meter
Temperature sensor (could be making the car think it is colder/hotter than it really is, and be making the fuel too rich/lean. Is the exhaust really black?)

I question as to why your mechanic recomended you pull the head and replace it. Was there something else wrong with it?

Featherlou-
For what it is worth the 80s and 90s Shadows/Sudances with especially 2.2L based engines are not exactly “icons” of reliablility. If it is starting to give you headaches (and if you can afford it!) you may want to consider parting company with your dear friend.

That is, of course, in my extremely biased opinion :wink:

You know, I keep thinking it’s a fuel problem, too - the car behaves exactly the way my old Nova did when I accidentally let the fuel filter freeze one winter (no gasline antifreeze in the tank, a winter trip to Banff - I think you know what I’m talking about, bernse :)). My mechanic doesn’t seem inclined to view it that way; maybe he needs a little gentle prodding to take this approach (I’ll ask him about the lambda sensor, too, casdave). Oh yeah, the exhaust looks fine - not blue or black or too much of it or anything. The gas usage seems fine, too.

(As for ditching the car (and don’t think it hasn’t crossed my mind), we are at a place right now where a bunch of circumstances have made this our only vehicle, with Jim just laid off, our wedding and the bills thereof less than a month away, etc. - in other words, bad timing. So the car, using its usual impeccable car logic, takes this opportunity to start acting up again. At this point, anything we could afford to replace this car would be trading these problems for a different set. Heavy sigh.)

Oh, as for the head replacement, I listed the things he had already done - I assume he has already replaced the head since he listed rebuilt head, gasket, and a set of head bolts on one of the bills for work done. It’s the usual story; he’s the mechanic, so if he thinks a rebuilt head will fix the problem, that’s what I pay for. I’m not completely mechanically inept, but I’m not knowledgeable enough to second guess things like that myself. I don’t think he’s taking advantage of me; my whole family goes to him, we have almost no complaints with him, and he knows he would lose a lot of business if we all walked. He could just be incompetent without being malicious, but I don’t get that vibe from him either.

I’ll second Casdave here. It sounds like it’s running lean. Getting a mechanic to replace the O[sub]2[/sub] (lambda, oxygen) sensor should be high on the list of things to do. Personally, I wouldn’t have done any engine work (a new head?!?!) unless the engine had high leakdown through the valves, and I doubt that running like this would be caused by a bad head.

Come to think of it, and as much as I hate to slag mechanics, how about getting another mechanic to replace the oxygen sensor.

BTW - Featherlou

These sensors (O2, temp, air flow meter) are all items that can get tested instead of just outright replaced, but they require the proper tools. If you have an “old school” mechanic that is great working in a 79 350 Chev with a 4bbl carb but kinda lost with newer EFI vehicles, well, you might have problems. A problem like yours should be easily solveble with the proper equipment.

Still, do the “easy, cheap things” first (IE - Filters) if they haven’t been done recently. Go from there.

PS - As I mentioned earlier (and Cornflakes just repeated), I really have a hard time understanding whey he did the head. Did it overheat recently in addition to this or something else…?

Get a new mechanic, post haste! It sounds like this guy is a parts swapper. That is someone who has no idea what the problem is and just starts swapping parts till it goes away. Not time/cost effective at all (for you, at least! this guy gets paid for every job he does!)

I would suggest fuel system also, based on symptoms. Check fuel pump pressure and for clogged injectors.

Good luck! (and buy European or Japanese in the future ;))


Damn! I have forgotten to not become drunken again!

Has the catalytic converter been checked? Or other than that, the only thing that comes to mind is the air flow sensor. Fuel injection is wonderful…'til it breaks. Give me a 650 Holley any day…:sigh:

AAGGGHHH! Imported cars!!! (Just kidding. I do understand that they are better built for the most part than the type of domestic car I can afford. It’s just that the parts for them are so damned expensive in Canada. Parts for a Sundance - not so much.)

So, it’s looking like the consensus is start with filters and sensors on the fuel/air systems. Maybe I should go to a different mechanic; my first instinct said this was a fuel problem, and I was very surprised when he worked on everything but the fuel system.

(And I really don’t know why he was messing with my head (pun intended) - I didn’t think anything of it at the time, but it’s sounding like something I should have questioned further. Unless I’m just misreading his garbled writing.)

I agree with the Oxygen sensor, if it’s giving the MAP or PROM wrong signals, the feul injection will screw up. My parents car was having similar problems and tey too went through new starters and almost everything. Then I came home and changed the O2 sensor and everything was great. :slight_smile: makes me feel needed and smart.

You want to come to my house and change the O2 sensor, **Clairific{/b]? I would make you feel needed and smart, I promise. Probably throw in a case of beer, too. And not American beer, either; I would go whole hog and spring for a case of good Canadian stuff. :smiley:

Hi featherlou,

Looks like there are a number of good ideas here but in reality, the oxygen sensor won’t likely be this much of a nusiance. Usually, Chrysler built vehicles have more of a tendency to start losing power at or near highway speeds if the sensor goes bad.

There is a series of tests that can be run on your poor vehicle with a factory approved device called a DRB. (Data Readout Box).

Chrysler vehicles built since 1983 have the ability to be “Scanned” if you will, by this device. If there is a problem with nearly any fuel injection component, e.g. MAP sensor, Oxygen Sensor, etc. it will be displayed on the DRB’s screen. You will have to schedule a session with your local dealer to have this done unless, you can find a repair shop that has one. (Chrysler did offer them for sale but most shops opt for the generic scanners that cover most brands with one scanner).

You apparently have covered a few of the common sources of trouble but, as it was mentioned before in someones post, Fuel Injection is a very big hassle for the untrained technician. Or, at least for the tech with limited resouces.

If I had to make a SWAG, I would probably be leaning toward the fuel system as well. I don’t know if your car is turbocharged or not so, that too can play into the picture of possible problems. If your car is not a turbo, there is a cool little home brewed trick involving a timing light and throttle body injection. Old timers will remember this one. If your car is a turbo then you’re out of luck on that one. Injector spray patterns ar sealed inside the intake manifold and cannot be tested this way.

You might have guessed it by now that I am a working technician for Daimler Chrysler. Correct! I have been since 1992 so I have seen a lot of the problems associated with these cars. My best advice would be to stop tossing parts at the car and, go get it looked at by someone who knows it best. You’ll spend a considerable amount less in the long run. No insult intended for your family mechanic but, he should stop spending your money and get the car fixed.