Ok I have a z6 in a 91 wagon rt4wd and it won't fire. I pulled the head and sent it to the machine shop where they found it warped and milled it for me. They also found the valve stem seal shot so the valves wouldn't seat properly. They fixed all of that and I put a new headgasket on it and got it all back together and the car still won't run. It will turn over and run for a split second then die. The compression before and after the head repair on cylinder 1 was 90psi. All the rest have about 170psi. So at this point I am pretty sure cylinder 1 is dead. Any opinions or second thoughts? Guess I'll be pulling this engine for a rebuild

 

did you torque your headbolts in the correct order and sequence? did you reuse old head bolts or buy new?

you should have bought new, honda head bolts are torqued to yeild which means they are not good to be taken out then reused

 

even with that low pressure in one cylinder it should have no trouble running. people reuse honda head bolts all the time so i dont suspect that is your problem. i would bet the issue is elsewhere although what exactly the issue is i can't be sure.

 

Yes I reused my headbolts and yes I torqued them down correctly and in the correct order using a Honda shop manual. I debated on getting new ones as I know old ones in that year had a bulletin for stretching but I'm pretty sure that's just on the 1.5 not 1.6. My main goal was just to see if it would fire. I went out just a second ago to try it again and had it in first and turned the key. Pressed the clutch pedal in and then bam clutch pedal went straight to the floor and now I can't get my clutch pedal back so I have 2 problems at this point.

 

I bought this car with the problem already existing so I may have to back track a little furter to see what's going on

 

the headbold stretching isnt a builten, its a material science thing. Honda designed the bolts to torque to yeild on purpose, its for all d series engines.

Your low compression then would probably be caused by either your piston rings or valves not sealing. Either way the car should still start, you have other problems that need addressed were ever they might be

 

if your clutch pedal is stuck on the floor the you have another issue other than your motor. Is your tranny hydaulic or cable. Since you have a z6 id assume hydraulic which could mean you have air or possibly no fluid in the line.

 

leakdown test

 

91 rt4wd is still cable

 

check to see if your cable is broken and if its still connected to the clutch pedal. secondly your car should still run with low comp in one cyl. check your fuel and spark and def timing.

 

busted clutch cable? I would tend to believe something with the cable/trans/clutch is the culprit of the running issue. Car would still run with bad compression. If you really believe the compression is an issue just pour a tea spoon of oil down the cyl and replace the spark plug then run it.

 

Do the compression test again on cylinder 1. You should expect your 70 psi.
Then do it AGAIN, but pour a cap full or two of oil into the cylinder through the spark plug hole before the test.
If your psi goes up significantly THEN you can positively assume you have piston rings and cylinder wall issues.

 

will do. I also have to see what the deal is with the clutch pedal and why it went to the floor

 

i am going to try a main fuel relay to begin with just to start some simple diagnostics. I've checked all fueses and nothing is blown at this point. Because if ti will fire and run for a few seconds then I don't believe the low cylinder is the direct problem

 

replaced the main fuel relay and the fuel pump and it still will not run. it will fire and run for a split second then die so now i'll go back and recheck the distributor and the ignition switch

 

Try to see if it will run on starting fluid if it does then you have a fuel issue.

 

How bout you check cam timing.

 

Have you tried oil in the cylinder yet?

Other post had a guy with a similar problem (good compression on all 4 though) that was able to fix the problem with spark plugs and plug wires.
Totally slipped my mind - how do your plugs look? They tell a BIG story if you can read them. Google for it. There is lots to learn from a spark plug.

 

ok i figured it out. cant believe it took me this long to figure it out but had some help from a good friend. turns out the distributor was a d15b vtec distributor rewired with the obd0 plugs but the computer was still the stock computer so of course it wouldn't run. So i changed out my computer to my p28 and used my conversion harness and bam it fired right up but the engine smokes very bad :-(. I am guessing because if that cylinder1 is still low it could be getting past the rings but I have not had much time to run more tests on it so i'll do this as I go.

 

its always the thing u check last