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Neon Compression test results, your diagnosis please????

09-29-2010, 08:24 PM
So I posted here about headgaskets. The owner said 3 and 4 cylinders had low compression. Headgasket blown between?


So then I found out that all cylinders have low compression. Starting on the timing belt side, compression goes 80psi, 60psi, 20psi, 0psi.

The car turns over fine, no knocks or ticks.

After finding this out I thought maybe the timing belt skipped. The car has 190k miles and I'm sure its the original belt. What else could cause compression readings like these?

A little background is the owners daughter was driving home and the car started losing power, she pulled over, turned it off, called for a ride (late at night), the next day the owner went back and tried to start it and got nothing. Turned over would not start. Upon me hearing it turn over, I know its turning WAY too fast as if it has no compression.

Today after work I started removing the side of the motor to check out the timing belt. Got up to the crank pulley, using a 3 jawed puller and I could not get it to budge, so I called it quits for the day.

First question is the compression results, what could cause readings this low besides the timing belt?

Second question, is this an interference motor? (2.0 16 valve the valve cover says)

Third question, anyone have any helpfull hints on getting the darn crank pulley off? And yes the bolt is loose, I'm not that dumb.

09-29-2010, 08:38 PM
It sounds like a bad timing belt, a interference motor would bend valves and make noise.

I would set cylinder 1 @ tdc, and check timing marks.
If Timing is ok, it could be just burnt valves,or a bad head gasket.

09-29-2010, 08:57 PM
It sounds like a bad timing belt, a interference motor would bend valves and make noise.

Thats what I thought too, but knowing my luck, they are all bent, all 16. The way my luck goes, I could bend valves in a non interference GM 350 pushrod motor.:grinno:

I would set cylinder 1 @ tdc, and check timing marks.
If Timing is ok, it could be just burnt valves,or a bad head gasket.

That is exactly what I am going to do, but if the headgasket were blown, how could it cause low compression on all 4. I guess here again, its just my luck.

Oldsmobile Doctor
09-30-2010, 07:48 AM
Auto Zone has a tool # 27139 to remove the damper

09-30-2010, 09:50 AM
Does it work and how much is it? There are no holes to screw into to use a regular dampner puller. I was just using a 3 jawed pulley puller and had no luck. Last one of these I put a timing belt in, I had the same issue. Dampner would not budge, I fought with it for a while and finally it went. Althought that time I was also just using the 3 jawwed puller.

09-30-2010, 10:45 AM
Auto Zone has a tool # 27139 to remove the damper

I looked it up and it looks excactly like the tool I am using.

Oldsmobile Doctor
10-01-2010, 07:13 AM
Look closer that one is special for Chrysler harmonic balancers. It comes with two pins that you put one or the other in the bolt hole depending on how deep the hole is.

10-02-2010, 02:21 AM
I got it off.

Timing is dead on perfect, in fact the belt looks like its been changed in the past.

I began pulling the head off to see if the head gasket blew or if the head is cracked or if it has lower end issues.

Couple questions though.

What is that sensor in the lower battery tray? I started to take the tray out, I thought it was a nut holding the battery in and I spun nut around and ended up snapping the wires. No big deal but it looks to me like some sort of temperature sensor.

And if anyone has any pointers on getting some broken EGR valve bolts out. I'll probably soak it for a few days and try a vice grips. Or a little heat.

Also when the time comes I'll need some torque specs on the head bolts.


Oldsmobile Doctor
10-02-2010, 08:20 AM
1st Tighten to 25 ft. lbs.
2nd Tighten to 50 ft. lbs.
3rd Tighten to 50 ft. lbs
4th Tighten an additional turn
(DO Not use a torque wrench for 4th step)

10-05-2010, 08:59 PM
Got the head off, piston 4 has a chip missing (hence the 0psi compression) and all 4 cylinders seem to have some scoring. Motor is toast. Looks like the car is going to get parted out and hauled to the junkyard.

If anyone needs any parts, shoot me a PM or an email. I'd rather not ship heavy things like the head or transmission (which was acting up towards the end I'm also told). But I have no problem shipping the smaller stuff it you cover the actual shipping charges and add a little extra for paypal fees.

More details on craigslist.





10-06-2010, 10:53 AM
What's the year and condition of car, other than a bad motor?
I gave my 95TC away, it had a bad engine and still have regreats.

* Pistons & rings on a 4-cylinder is 50% cheaper than a V8.

10-07-2010, 10:19 AM
its a 95, a little over 160,000 miles if I remember right, the windshield is cracked, paint baked off the roof, back corners of the body are rusted out, front bumper cover is cracked.

It was a 500.00 car 2 years ago.

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