Engine problems w/ partial diagnosis
#1
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Engine problems w/ partial diagnosis
Here we go... My car has had engine trouble for the past month or so, and I finally have enough cash to get it fixed, and I'd like to make sure I know a little of what I'm talking about with my new mechanic.
I know it needs the valve stem seals replaced since it's eating oil and has a healthy plume of bluish-grey smoke at idle and off the line. Since he'll be in the cylinder head, what else needs to be looked at for wear & replacement?
Also, the throttle is currently extremely jerky in the low rpms, but smooths out after about 3500-4000. I have a few possibilites of causes:
1. I recently replaced the O2 sensor; the data controlling fuel mixture is getting distorted by the burned oil passing through the exhaust system
2. I remember reading a post of Alex's (Audi_80) that this happened to a friend of his; I think he said the timing belt had jumped a notch or something.
3. One or more spark plugs are fouled and are not sparking on every revolution
Am I correct in thinking that the valve seal job should fix any of these problems since the T-belt has to come off to get into the head? Do these reasons sound logical? Any other thoughts or things to look for? TIA
-Wren
I know it needs the valve stem seals replaced since it's eating oil and has a healthy plume of bluish-grey smoke at idle and off the line. Since he'll be in the cylinder head, what else needs to be looked at for wear & replacement?
Also, the throttle is currently extremely jerky in the low rpms, but smooths out after about 3500-4000. I have a few possibilites of causes:
1. I recently replaced the O2 sensor; the data controlling fuel mixture is getting distorted by the burned oil passing through the exhaust system
2. I remember reading a post of Alex's (Audi_80) that this happened to a friend of his; I think he said the timing belt had jumped a notch or something.
3. One or more spark plugs are fouled and are not sparking on every revolution
Am I correct in thinking that the valve seal job should fix any of these problems since the T-belt has to come off to get into the head? Do these reasons sound logical? Any other thoughts or things to look for? TIA
-Wren
#3
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And if it ends up being seals
When you get the head done, just have them do a standard head job. Check the seats/grind them.
Go ahead and look at the plugs while doing the teardown, you should see right away how they look.
Check the dist gear while it's apart.
Go ahead and check the timing marks before it comes apart, just to satisfy yourself one way or the other, but for sure do the belt. It's cheap and should be changed anyway, now's the time to do it.
Go ahead and look at the plugs while doing the teardown, you should see right away how they look.
Check the dist gear while it's apart.
Go ahead and check the timing marks before it comes apart, just to satisfy yourself one way or the other, but for sure do the belt. It's cheap and should be changed anyway, now's the time to do it.
#4
Re: Engine problems w/ partial diagnosis
seals really don't do much other than seal the oil from seeping down onto the valves and getting burned in the cylinders. You should look at the ignition wires, and the vacuum lines first.... But first look to see if your timing is right on. Sounds like you might have a vacuum leak problem. You've got to make sure these things are all within reasonable working life:
Rotor
Dist. Cap
spark plugs
air filter
fuel filter
fuel pump
spark plug wires
(clean your ISV)
Fuel injectors are spraying proper pattern and not dripping.
Rotor
Dist. Cap
spark plugs
air filter
fuel filter
fuel pump
spark plug wires
(clean your ISV)
Fuel injectors are spraying proper pattern and not dripping.
#7
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It only hesitates under light acceleration...
If I mash the throttle, it pulls hard all the way up. It also idles at a very stable 800rpm. Wouldn't a vacuum leak cause a choppy idle?
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#8
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Thanks. It might be the fuel pump going out... It's been pretty loud recently
Of course, it's hard to tell over my exhaust, or lack thereof. Once my engine stops blowing oil out the tailpipe i can finally get a new system that actually has a rear muffler (previous owner removed it)
I'm thinking of copying the miktip special for 20v w/ 2.25" pipe, catco cat from summit and magnaflow 14415 and 14335 mufflers.
I'm thinking of copying the miktip special for 20v w/ 2.25" pipe, catco cat from summit and magnaflow 14415 and 14335 mufflers.
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If the plugs
are fouling with oil, they sure will make a big impact. The car will indeed stumble and miss.
With a big blue cloud, fouling is appears pretty evident.
With a big blue cloud, fouling is appears pretty evident.