Running on a couple cylinders

[Gforcefd]

Okay so a couple of weeks ago my car overheated after the radiator split and blew another headgasket.

I tore everything down the head was fine, and straight. I put in a new headgasket and I have 120 psi+ in all the cylinders. The car is idling ruff and only seems to be running on cylinder 1 + 4.

I am guessing this because while having the car running I pulled the spark plug wires one at a time from each cylinder and the car only ran ruffer on 1 + 4 (indicating they where running fine, where cylinder 2+3 had no effect when there plugs where removed...

I pulled the plugs and they look good, completely dry. I was wondering if this could mean a fuel issue?

Just looking for some ideas so Brian can buy my yellow beauty :-P

Logan

[MONSOON]

Are the injectors squirting like they should?

[GenevaDirt]

shouldn't it be more like 180 psi across the board? And I would check the injectors if everything else is hooked up right.

[festivaWES]

yeah 120 is low even if the compresson test was done the a warm engine...mine hit 155 accross the board cold.

[Gforcefd]

I thought 120+ was normal? That was after quick cranks without it starting but maybe I am wrong how I did it.

I was wondering if the heat could have done something to the injectors even though they are in the intake and not in the head... I will have to check tomorrow.

[Gforcefd]

It is a low mileage engine (67k) did I possibly hurt something else besides the head gasket when it overeheated?

I checked the head and it was flat and did not look warped.

[festivaWES]

120 is almost a number i would consider rebullding the engine at.

[FB71]

did you measure the head's gasket surface with a machinist's straight edge and feeler gauge? It should be less than 0.001" per 12". In my experience, if these engines overheat, the head warps about 0.003" - 0.005", enough to cause sealing issues and low compression. Also, overheating causes the rings to loose tension, which will lower the compression readings.

[Gforcefd]

Ugh..... Maybe I should just grab another engine at this point. Its not looking good.

[25Horseplay]

I would buy it as is if the price is right!

[Gforcefd]

Ugh.....Brian I would love to sell it to you, but I can't afford to take a loss on it, unless my spirit breaks. I am going to try and find another engine I think.

[25Horseplay]

Just deduct the cost of the engine and your time and you'll still be ahead!

[jglutz]

Ugh..... Maybe I should just grab another engine at this point. Its not looking good.

Hold on......
Your comression readings.....120psig...accross the board are not that bad for a cold engines.....Reaching 180psig takes a warm engin and 3-5 comression strokes. They key clue you provided is that the readings wher accross the board....if 2 and 3 where bad and 1 and 4 are good...why would the readings be all the same if thcylinders behave differently?

A quick ring test is to use the hose from the compression tester to inject air from an air compressor. Set the cylinder to be tested at TDC...inject the air from the compressor thru the hose. The cylinder should blow quickly down. Then listen for the air blowing by the rings. A cylinder with bad rings will sound distictly different.

Are the ignition wires connected correctly?

Is the rotor is stalled properly?

Is the base timing set properly?

I would do all of the above before thowing in the towel.

[CharlieZ]

120 sounds low and all four cylinders being exactly seems improbable.
Why not run a cylinder leak-down test a.k.a. cylinder differential test for one more bit of data?

[Gforcefd]

I said 120+ they are not all identical. I don't own a air compressor so I can't do a leak down test right now. Thanks for everyones ideas, they at least point me in the right direction I think.