compression testing

[dakmon]

I went to test the compression and could not determine how to unplug the coil pack to avoid shock. Could someone please let me know which connector powers the coil pack. Yes I did check my manual but it is not very descriptive.

Thanks in advance.

 

[98RedGs]

http://www.dsmgrrrl.com/FAQs/compression.htm

 

[dakmon]

Thanks for the input 98RedGs. I do know the location of the coil pack, I am just unsure as to what I am to unplug. The FAQ photo is somewhat helpful but it is not clear to me if this is a quick connector right beside the plug wires. If it is could you tell me which wire it is closest to.

Thanks

 

[kpt4321]

Normally it's a triangular plug, but you have a 90 so yours will be different.

There are two plugs, the higher one is the one you're looking for.

Or unplug the wires.

 

[dakmon]

Thanks, kpt4321, I will look for that plug tomorrow.

 

[LeoGSTSpyder]

Thanks for the guide it worked like a charm for me. Someone please tell me if I should do something about the below numbers:

98 GST Spyder with 60,000 miles

Cylinder one(passenger side) : 185, (210 wet test)
Cylinder two : 160, (190 wet test)
Cylinder three : 160, (190 wet test)
Cylinder four(drivers side) : 168, (200 wet test)

I checked the plugs and all of them were running a hot with a little ash deposits. The plug from number one was the cleanest.

The guild says you should have more then 14 PSI difference between cylinders, so should I do anything about these symptoms before I start adding intake and exhaust?

 

[1fast97gsx]

looks like you need to take the engine apart ... it's not too bad but its not consistant. Having a 185 and 2 160s is a huge difference. You might just have those rings wearing out faster but either way all 4 should be close. I have a 97 gsx and it got 175 175 176 176 and it also has 60k on it ... they are 178 from the factory.

 

[RipperXX]

Yep, time for a rebuild...


lord knows I need one..

think of these #'s

#4 132
#3 120
#2 120
#1 122


keep in mind that was on a cold engine.. so add about 15psi I asume. oh and my engine has 190,000 and never been rebuilt

 

[kpt4321]

He doesn't necessarily need a rebuild. He does, on the other hand, need to clean the carbon out of those cylinders!

 

[LeoGSTSpyder]

How much is it to have a rebuild done/do it yourself? I thought things like that were VERY expensive?

If they are 178 from the factory, then how did my 1st cylinder get a 185 rating?

Does the rebuild protect anything or just restore some lost power?

 

[kpt4321]

Originally posted by LeoGSTSpyder
If they are 178 from the factory, then how did my 1st cylinder get a 185 rating?

Higher static compressio ratio due to carbon buildup, or a gauge that reads too high.

 

[rph74]

Originally posted by LeoGSTSpyder
How much is it to have a rebuild done/do it yourself? I thought things like that were VERY expensive?

If they are 178 from the factory, then how did my 1st cylinder get a 185 rating?

Does the rebuild protect anything or just restore some lost power?

It's surprisingly not too hard, I just replaced the pistons rings on mine, and had the head rebuilt. The total cost when all is said and done will be $500. To have everything done by a shop will be between $2500- and 3k. You can change the rings out while leaving the block in the car still.