ignition prob

[kevin]

i just got my tta runnin a couple weeks ago and ran really great,now the car started cutting out when tryin to build boost,changed coil pack and ignition mod with a known good one still the same,changed plug wires and then could build boost but after 10# it acts like somethin is grounding out,like 1 cylinder.my blm is 139 at idle af is 7.also changed mass air no luck,checked the grounds and cant find it.any ideas?

 

[83ttypecooled]

Hi,
How's your fuel pressure? I have a feeling you are dealing with a lean misfire. Our cars don't like it when you stomp them and there is no fuel to back it up! If you check it out,and this is not so, suspect a crank sensor issue. Goodluck with your trouble.

 

[kevin]

fuel pressure is ok but when you said crank sensor you may have hit the nail on the head,when i first bought this car the harmonic balancer came off well broke off and im using the same crank sensor so maybe it got damaged,i'll try it thanks

 

[kevin]

ok crank sensor didnt fix im outa ideas

 

[GNRick]

If the car sputters under acceleration check your TPS volts with a scan tool. Make sure they are increasing.

 

[Razor]

Bad chip?

Crank and cam sensors either work or dont.

Bad ECM?

Bad wires/plugs? Should be first on my list.

 

[TurboBuRick]

Crank and cam sensors either work or dont.

Not always the case. They can cause drivability problems like described. Specially if the balancer came loose again. No?

 

[Razor]

Not always the case. They can cause drivability problems like described. Specially if the balancer came loose again. No?

If the balancer came loose, the reluctor ring would not go through the window on the sensor and the car would shut off. This is not a bad sensor when this happens. It either works or doesnt. Not a part to develop intermittants unless full of oil/goo/or other debris. There is no moving part inside the cranksensor.

Only real issue its mal adjusted and makes contact with the balancer ring.. ting ting ting is what it will sound then.

So there is no drivability issue with a crank sensor unless it doesnt work becuase of other issues... but then its not a bad sensor but a loose balancer

 

[GNVenom]

I have seen problems where the crank thrust bearing goes out, causing the crank to move forward under acceleration - causing the interrupter ring for the crank sensor to "fall out" of the sensor path.

The spark shuts off under heavy acceleration, then resumes when you release the throttle.

Otherwise seems to run normally.

That problem will drive you crazy until you open the engine and find the damage to the bearing.

 

[kevin]

checked the tps and its ok.will check balancer bolt,it has the roller cam that was in the old block,i put the lifters in the same hole.i just read another post about bad cam symptoms and it sounds allot like what ive got going on,oh razor,i changed chips and does the same.is a buick ecm the same?if so i could take the 1 out of my t.thanks

 

[kevin]

changed ecm,no luck,balancer bolt is tight,im going to do a compression test and see whats goin on,this sucks

 

[kevin]

found it

had a spark plug not gapped right and blowing out the spark,yes i feel retarted