Problems After Head Gasket Replacement...

[CAJUN-Z]

History: Purchased '96 Deville 134k miles beautiful condition. Overheated and went into protection mode shortly thereafter. Pulled heads...machine shop resurfaced and reworked heads...everything put together and timeserted...torqued...engine studders and won't idle. Scanner shows map sensor out of range and injectors misfiring. Pulled cover and checked cams and timing...everything dead on. Checked spark...fuel pressure...spark plug wire positions, etc. everything dead on. Emission problem scrolls in info window on dash. Anyone have any imput on this?...
Someone please help before I get my pistol and shoot this 4.6 to death!...

[BeelzeBob]

When you say "Pulled cover and checked cams and timing...everything dead on. " what do you mean?? Was the front cover pulled to check timing of the primary chain AND the two secondary chains.

When the number 1 cylinder (right front) is at TDC firing (which you can determine with a piece of wire/dial indicator thru the spark plug port) are all four cams timed with the reference dowels in the cams at 12:00 relative to the cam cover sealing surface? Are all four sprockets installed correctly using the "intake" slot if it is on an intake cam and the "exhaust" slot for exhaust cams?? The sprockets are common among the left and right bank but you have to use the RE timing slot on the right exhaust cam and the RI on the right intake cam...each sprocket has both slots.

It REALLY sounds like the cam timing is messed up and/or some valves were bent in the process of the repair.

If heads were installed with the cams randomly timed and then the engine was turned over and the cams rotated to time the sprockets it is VERY easy to bend a valve as the valves will certainly contact the pistons if they are out of time during assembly.

If you are certain of the cam timing then run a quick compression check of all cylinders to make sure if they all have good compression and are similar. My bet is that you will find the compression all over the map.....

[CAJUN-Z]

Back head sprockets off one tooth on chain. No compression on cylinder 1-3-5-7 check. Retimed and runs like a raped ape. I'll put the pistol back in the holster...
Thanks...

[CAJUN-Z]

A bud of mine purchased a new ion redline (supercharged) and challenged me to a "sporting event". He claims when it turned appx. 1000 miles he took it to the track and turned a 13.97 @99.4mph. I took him up on his challenge and pulled him 1.5 cars from a 20 roll and 2.25 cars from a dead. He was quite surprised what a big grocery-getter can do to a supercharged (5-speed) Saturn....
Just thought I'd share...

[an01sts]

These ol' Cadiracks surprise lots of people when the battle light flashes. I notice that you list a 90 GT. How does the ol' geezer car do against that one?

I know it sounds odd--and I, too, found it quite surprizing--but my STS smokes some of the GT's on the road. Not all, but it smokes many. Well, maybe not smoking them like it smokes rice burners, but they're definantly looking at the STS logo.

The expression on the face of the driver of a rice burner who just got toasted by an STS: Expected.

The expression on the fact of the driver of a GT who just got toasted by an STS: Priceless.

[CAJUN-Z]

Originally Posted by an01sts

These ol' Cadiracks surprise lots of people when the battle light flashes. I notice that you list a 90 GT. How does the ol' geezer car do against that one?...

Never had the opportunity to try out the Mustang against the north*. The mustang is pretty quick (5-sp. w/3.73:1 rear) but on a run longer than the 1/4...I thinks the mustang will have a problem...