im ahving a problem and need to know what it is...i just sanded out, dremeled my throttle body, all seems good, but when i turn off the car, it has a shudder at the end of it, i dunno what it could be though, any suggestions, any ideas wat to sheck out...would it be the tps????

Don't really know, but I would guess maybe a hot engine burning excess fuel?? Sounds a lot like something my old XD falcon used to do. it was pretty worked, and run real hot. did this funny sorta shudder when you turned it off. like the ignition was off, and it almost stopped, then all of a sudden it would fire again on one or two pots before it finally died.

dunno what it actually was, did it all the time, never hurt it, still goes hard. (mind you that motor was ***kin indestructable!!)

not sure what this would be on a magna.. how hot does your motor get??

Cheers,

yeh the motor gets pretty hot ewy, and it smells like out the exhuast it has a really smelly petrol smell...like pertrol is in the exhuast and hurts yah nose, smells weird.....never done this before though??? wat changed ur fuel and air regulation, also could it be sprak plugs or leads.....??????

mite b just excess fuel goin to the engine just prior to switching off...as the engine is still very hot, the excess fuel would burn up...so yeah....my old bomb used to do this too....i'd like an explanation for this too

As far as I know, and someone please correct me if im wrong, this is called overrun, and is caused by excessively hot plugs. This usually happens when the engine runs lean which creates heaps more heat in the cylinders. This would make sense if it happens after increasing air flow to the motor by modifying the throttle body without getting more fuel in.

Be careful because this could very well also be causing pinging and seriously affect the life of the motor!

Perhaps try resetting the computer, this may speed up the learning process and get it to put some more fuel in.

Overrun is correct - caused by either hot plugs, or excessive carbon buildup in the upper combustion chamber...

Cheers
Heath Young

Overrun is correct - caused by either hot plugs, or excessive carbon buildup in the upper combustion chamber...
CheersHeath Young

The latter, I'd say.
Check that the TB BF closes properly. Was there any such bad action before the TB work? TPS? Mmmmm, not really, but play with it.
Coincidence? - check plugs and use good fuel and injector cleaner.
Yep, good idea to reset ECU too.

well i actually figured it out, the tps wasnt plugged in properly, this was the problem, also my plugs alwasy seem to **** up on me, no matter what brand , they seem to always lose the middle, no mater how careful i am......

If you are chewing up plugs, especially NGK you are either running lean which is very dangerous or your plugs are the wrong heat range.

Get the exhaust gas analised to get a reading.

My car does this too. Its only when Iv been driving hard then turn the car off without letting it idle for a few seconds or if I turn off with the choke out a bit. I think its just because of carbon buildup and/or lotsa fuel still running out of the carby. Usually letting it idle before switching off for 7 or so seconds stops the problem.

Overrun is correct - caused by either hot plugs, or excessive carbon buildup in the upper combustion chamber...

Cheers
Heath Young
really? i always thought it was called 'running on'

which the TB alignment, there are two switches in there. One is the potentiometer for a throttle read out and then there is either a WOT or a closed throttle switch. i think ur TB is out a little and its running in because for a second durring shut down the engine is fueling a tiny bit because it thinks the trottle is open.


happened a few different times to me :confused:


also rig up a cheap water injection setup for a few days to steam clean the insides of ur engine.