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Told my Engine needed replaced!!!

Tammythomas68

New member
You guys seem to know alot and I need help. :(

I have a 2002 3800 non SC and I have had alot of small issues. I bought the car in July this year.... Right off I heard what I think was a lifter ticking..but no big deal, then the car started bucking, but only every once in a while and I was told it was probably a O2 sensor... Dont really worry, then it got worse and I took it in the shop... It come up Cylinder #3 was misfiring, so the checked compression and Cylinder #3 showed very low compression. I get a call that I need to have the engine rebuilt!!!!! Really???? Is this right??? I was told it "probably" overheated at some point and needs replaced/rebuilt. I know things happened before I got it but it makes no sense to me.... Just cause you have a bad cylinder you have to rebuild the entire motor??? Please give me advice!!!
 


you dont have to do anything. but i wouldnt trust the heads or the rest if there is reason to think it overheated to the point a #3 is dead.

Rebuilding an engine is not recommended. a bottom end is cheaper and will be better in the long run. too much room for error/ problems to open it all up.

if you want a SC'd engine now would be a good time. you could prob find one for not much more then a complete Na.

sorry to hear about it all though. it sounds like you got someone else's problem car. i just recently had to replace my engine. my DOHC had 224,000 miles on it and finally gave up. i used the opportunity to swap to the l36 and get a topswap kit. once its all done i'll have much more power then i had for about the same price as i would have paid for another DOHC
 
Are you able to verify the shop's findings yourself? Bad plug/wire/coil pack can cause misfires on one cylinder.

Go to parts store. Buy a tune up and rent a compression tester.

Let the car warm up , pull the plugs, check compression yourself If it's truly lower than the rest, then return everything you bought and consider alternatives
If not , install new plugs wires and possible coil pack. Test drive
 
I'd have someone check the wires and plugs. Low compression is low compression all the time. Not just an intermittent symptom.
 
I'd have someone check the wires and plugs. Low compression is low compression all the time. Not just an intermittent symptom.

THIS.....


If you truly have low compression (which I would ALWAYS check for myself) How low is it... there is an acceptable range of "lowness" before it becomes problematic. But if you have REALLY low compression on that cyl. Then yes you will prolly have to rebuild/replace the motor. Most guys just buy yard motors for their cars, if you have the skill set needed I would rebuild it. But that is me and I have the tools. But first thing is first. Buy a compression tester and test it for yourself. Mechs. are a lot like Politicians. They will lie most of the time if it helps them and they dont think they can get caught.
 


Was a dry wet compression test done?

A normal dry compression test only tells you about low compression while a wet test can pinpoint the problem to heads or rings.

Put a few squirt of motor oil in #3 cyl and do a compression test. Do it a couple of times. As the oil seeps into the area around the piston it seals the rings allowing for better compression. If the compression comes up, it's the rings, if it doesn't, it is probably the heads/head gasket. The head can have a burnt valve which would give low to no compression, depending on the severity of the valve problem.

Is there oil in the coolant (It will appear light brown in color) or spots of oil in the coolant?

Does the car overheat? Did it overheat since you have had it? Do you lose coolant? Was the check engine light on? If so, what were the codes, these are things the garage should have told you.

While the engine is running, pull the wire off cyl #3 (do it from the coil as it's easier to access it. Also, use rubber gloves or pliers with insulated handles) and see if there is a noticeable difference in how it runs.

How many miles on the car? It is not unheard of to get over 200,000 miles (340,000KM) on a 3800 as they are really good engines.

Let us know,
Ian
 
You might wanna get a second opinion. What many people claim to be the mechanic lying is more likely the mechanic guessing.

A cylinder with very low compression will misfire, this is true. If the misfire is intermittent then i would expect the low compression to be intermittent as well and be a symptom, not a cause. Have the wet compression test done and see if the compression comes up. See if they will tell you the actual numbers from thier compression tests.;)
 
Wow, you guys know your stuff.... First off im a girl, so other than the basics...i leave it to a friend of mine. This time I thought rhe problem was bigger so I took it to a shop in town, very small town... He actually acted as if he didnt have the time for it... So my friend can hopefully use all ur advice im printing to help.

The car has 203,583 miles and ive only had it four months.... I just dont really think its completely abad motor. The misfire it very apparent upon starting and/or idling.... Other than that, youd never know it had it.. Its never cut off on me or not started, even at 20 degrees. I check all my fluids very regularily, being its a used car...tho the power steering is quite hard to get to. I am not sure if he did the wet compression test, but I bet NO.... He never told me the compression rate in #3 but I think the code the computer said was P0303.... I will keep you guys posted, I was told I can even keep driving it, makes no sense, course im not driving it tho... Im starting the detective work in the morning.... You guys are the BEST!!!!
 


Was a dry wet compression test done?

A normal dry compression test only tells you about low compression while a wet test can pinpoint the problem to heads or rings.

Put a few squirt of motor oil in #3 cyl and do a compression test. Do it a couple of times. As the oil seeps into the area around the piston it seals the rings allowing for better compression. If the compression comes up, it's the rings, if it doesn't, it is probably the heads/head gasket. The head can have a burnt valve which would give low to no compression, depending on the severity of the valve problem.

Is there oil in the coolant (It will appear light brown in color) or spots of oil in the coolant?

Does the car overheat? Did it overheat since you have had it? Do you lose coolant? Was the check engine light on? If so, what were the codes, these are things the garage should have told you.

While the engine is running, pull the wire off cyl #3 (do it from the coil as it's easier to access it. Also, use rubber gloves or pliers with insulated handles) and see if there is a noticeable difference in how it runs.

How many miles on the car? It is not unheard of to get over 200,000 miles (340,000KM) on a 3800 as they are really good engines.

Let us know,
Ian






The car has never overheated on me, nor been missing any coolant.... Could use a radiator flush tho, but that I can do... Check engine light did come on on a sunday and when I left fir the shop on monday it was blinking. Stopped to get gas and when I turned it back on it was not blinking and has not blinked since... The low coolant light stays on but its never been low..... Im starting to think coil pack possibly!!!
 
The car has never overheated on me, nor been missing any coolant.... Could use a radiator flush tho, but that I can do... Check engine light did come on on a sunday and when I left fir the shop on monday it was blinking. Stopped to get gas and when I turned it back on it was not blinking and has not blinked since... The low coolant light stays on but its never been low..... Im starting to think coil pack possibly!!!


Checking to see if the coil is causing your problem is very easy. There's three coils on your car and each coil fires two cylinders. Under the hood looking at them, the spark plug wires are in order 6-3-2-5-4-1... starting furthest from you (top) and coming tword you (bottom).

Remove the wires from the top and center coils. Inspect the tips where the wires snap onto them, they should be clean, no rust or grey build up. Look inside the wire ends, same thing here, they should look clean. The wires should have a "snap" feeling to them when attaching them to the coils. If the connections look good then remove the top coil (this fires cylinders 6 & 3) and the center coil (this fires cylinders 2 & 5). Each coil as two little bolts holding it on, it takes a small socket, like 5.5-6 mm or something. Swap the coils, installing the top coil into the center position and the center coil into the top position. These coils are interchangeable, the numbers on them are for easier identification when installing plug wires. Now put your wires back on, not paying any attention to the numbers on the coils. The wires still need to be 6-3-2-5-4-1, top to bottom. Now run the car and see if the misfire is still coming from # 3. If it is, you eliminated the coil as cause, for no money invested. If the coil was causing the misfire, your code will now be P0305, misfire cylinder # 5.

BTW... if the engine light is blinking while you're driving, you have a bad misfire at that time. The car is warning you that you may be damaging the cat converter.
 
I am so grateful for your instructions and help... Its so AWESOME!!! I love my car and I am hoping to save her.... Ill be printing all this off and digging into her in the morning... I cant tell you thanks enough!!!
 
Tammythomas68 said:
The car has never overheated on me, nor been missing any coolant

Hi Tammy,

This is a very good thing. If no coolant is missing, I would rule out a bad head gasket.

Tammythomas68 said:
Check engine light did come on on a sunday and when I left fir the shop on monday it was blinking. Stopped to get gas and when I turned it back on it was not blinking and has not blinked since

The engine light on some cars flash in a certain pattern depending on the code (this is more common with air bag lights though), also, an engine light can go away on it's own, so this is not a concern.


Tammythomas68 said:
Im starting to think coil pack possibly!!!

I would agree with you on this from what I have read. Follow rocknnachos' directions and switch two of the coils and see if the misfire in a different cylinder.

I'm sure you'll figure it out.
Ian
 
The engine light on some cars flash in a certain pattern depending on the code (this is more common with air bag lights though), also, an engine light can go away on it's own, so this is not a concern.

I just wanted to touch on this. The engine light on these cars flash when there is a steady misfire detected by the PCM.

These guys are giving you good advice. What I would do first is start with the coils, if no corrosion is found on the terminals, swap a coil with the one on the affected cylinder and see if the misfire moves with the coil. I would also pull the spark plug on cylinder 3 and compare it to one of the other cylinders.

Also touching on the topic of compression, no one has yet mentioned possible causes of loss of compression in the cylinder head. Could be as easy as a broken spring, burnt valve. Not necessarily needing an engine rebuild.
 


I swear I cant thank you guys enough..... I was devistated thinking my car was shot...im thinking the shop I took it to didnt want to worry with it and just said that to get me out of thier hair... I am soooooooooo grateful to you all, I owe you all, bigtime!!!! Im hoping we get to work on it today, our roads here are flooded....
 
The guys are giving some good info/advice for sure.

Since the issue is only on the #3 cylinder: I'd start by swapping the wires are the coils between cylinders 3 and 6 to see if the issue moves to 6. It's not super common, I have though seen an ICM (ignition control module, part under coils) fire only one cylinder of the coil in the past. Each of our coils fires two cylinders, which is why you can swap 3 and 6 w/o worries.

Head gaskets are pretty rare to go bad on this motor. However it is a gasket.
 
Having a headgasket failure without any other symptoms is nearly impossible...

I would venture to guess that the head is broken... It has been a fairly common fix I have done in my little shop a few times now. These 3800 heads are pretty much junk on average.

Bonus is new n/a L36/L26 heads can be had for next to free, and the job is not at all that hard to do. You would proably have about $150 into parts, and 6-8 hours labor (not sure if you are a mechanically minded girl, but the average backyard guy/girl with a $50 tool set can do a head swap without much issue.)
 
OH4CompG; said:
no one has yet mentioned possible causes of loss of compression in the cylinder head. Could be as easy as a burnt valve.

I did, I did.:D

Tammy said there is no loss of coolant, so a headgasket is almost ruled out. Also, she mentioned this is somewhat of an intermittent problem as it is more noticeable on idle and start-up so a burnt valve is also ruled out. An electrical problem will cause this.

Ian
 
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