2005 Cavalier (2.2 ecotec) with new:
Fuel pump (50psi prime 65 psi during crank)
New fuel filter
New Spark Plugs
New timing chain,tensioner, guides,
New valve springs
New lifters
New Rockers,
New Vale Seals
New crank seal, and harmonic balancer
New belt and pulleys. (possibly other stuff that i'm forgetting)

Compression test dry (120/120/110/120) PSIG (open intake @ +13vdc) {MIN 100PSIG MAX DEVIANCE 70 %}
Spark gap (strength) observed @ over 1/2" to ground. (on coil pack)

I did a valve seal job and replaced all the worn stuff while I was at it. Motor was running rough @ idle 500-700 bouncing/surging,
Tore down to timing chain to inspect and reset just to make sure - no difference. (3ed time was not the charm)

Timing marks were
crank @ TDC 5 oclock dot to mark
Intake to 2 oclock and exhuast to 10 oclock.

Since the cams were removed - the cam lobes of cylinder 1 were set to TDC on Compression stroke. (from all the references I saw no lobes should be depressing the valves during TDC) The other option is 180 degrees and that would be on the intake stroke. So i believe i got it right. but maybe you know otherwise? (Also compression is good)

After starting and running for 30 mins of so with no computer adjustments (still running rough). I cleaned all the grounds then sprayed carb cleaner to find possible vacuum leaks - spayed some into the intake then the engine stalled and will not restart.

Intake has been pulled apart and cleaned, IACV has been removed and cleaned with electrical cleaner.
I have confirmed voltage @ each injector. Measured resistance of each injector 12.5 ohms.

I don't have a dc amp clamp so I can't measure pulses of current for the injectors. (this also would verify if the PCM is switching the ground contacts properly or not)

All fuses have been checked.
NO CODES ARE PRESENT / NO ENGINE LIGHT

Any other suggestions like getting a guy with a snap on reader to reset everything and chart the mixtures?
Buy a new PCM?
Or possibly another reset procedure (other then disconnecting battery for extended time frames)

Any help would be much appreciated.

Crank Position Sensor giving signal?

What is your altitude? 120psi seems really low, you should be well over 150psi. I believe usually in these engines its around 180. Are you sure you have the intake and exhaust gears facing the correct way?




On the inside my car looks like a fighter jet.

Elevation: 1,180 m (3,870 ft)
I'm sure that I got the cam gears on properly.

New Development:
Engine is flooded - when I remove the the fuel pressure relay and remote start the car I can get it to start. (when fuel pressure gets low like 10-20psig I plug it back in and she runs rough)
Fuel pressure is 50psig but when I let it drop to less then 30psig I will start up.

I don't think its a stuck injector - I confirmed electronic pulses with DC monitor and stethoscope.
The fuel pressure regulator has been replaced just in case with no change.
This car was working okay (blowing smoke) before this work was done - running smooth.

crank position sensor was giving a signal.

Titus K wrote:crank position sensor was giving a signal.

Scope your cam and crankshaft signal sensors at the PCM connector. Look to see if the sensor timing is completely off, when you compare both wave forms. Never check these
Sensors using a code reader or a multimeter.


ASE Certified Technician (A1,A4,A5,A6,A7)
DiamlerChrysler Certified Technician
Volvo/Ford Entry Level Certified Technician
Hyundai Motors Bronze,Silver and Gold Certified Technician
Option D Racing Member

I know you cleaned the iac but make sure its actually functional, take note of its position of the spindle on the way out. You have fuel and spark and enough compression to run it so its gotta be getting choked somewhere. Check all of the intake, if the tps is bad/ it may not run at all.

Its an old car! With lower compression. Make sure that your catalytic converter isnt plugged either.

If it runs with lower fuel pressure but not higher than it sounds like injectors to me. Namely too much pressure= too much gas. The regulator may be bad regardless of being replaced.

You could have a vaccum leak somwhere! Screwing the tps and pcm into mixtures that wont run.

Change the fuel filter.