VT Ecotec Stalling

[jacko1472]

Hey guys.

I have a VT series 2 ecotec (auto) that has been having a few issues lately. The car will at basically anytime while running randomly start revving up (to about 1200rpm) then rev back down (to about 300rpm) repeat this process 3-10 times. Sometimes after this happens the engine turns completely off and struggles to restart. This happens modestly when the car is idling (for example foot on brake at the lights) however has happened under load as well. The engine when working is running very smooth with no obvious missing or anything else. This problem seams to happen when the car is cold though not exclusively. This doesn't happen every time the car is driven however is becoming more common. The problem also doesn't cause any engine lights to come on. So far i have had the car on the diagnostic computer (bridging the diagnostic port was showing nothing but code 12 'no faults') which yielded a crank angel sensor code. The crank angel sensor was replace (along with the harmonic balancer and the belt). Since replacing the crank angel sensor the diagnostics computer once again shows the same error (crank angel sensor). Also just fitted new spark plug leads. Have checked all obvious solutions and am out of idea's. Any suggestions?

Thanks in advance.

 

[SKDSLT]

Have you checked for any vacuum leaks? Have you tried swapping the coil packs over with a known working one?

Is it using coolant? Might pay to get a pressure test done, rule out a cracked head(s) and/or inlet manifold gasket.

 

[HTV1900]

Try cleaning the iac solinoid. There is a how to thread on here somewhere

 

[Cashman_309]

Clean IAC and MAF. Search how to do this.

Check all pipes you see on the engine for signs of deterioration, replace as necessary.