Engine Hesitation Help

[Arnott(VY)]

To all reading,

Today my engine hesitated a couple of times upon accelerating (revs went funny), however no 'check engine lights' came on etc. I also felt a slight thudding, through the seat, somewhere in my car.

I have a suspicion that it is due to me changing fuels. I have used regular unleaded the whole time ive owned the car, and only a couple of days ago decided to give E10 a go. I have only used a quater of a tank and am just beginning to see the hesitating (or flat spot) effect in the engine. I was wondering if anybody reading thinks that not using E10 would save me having to go see a mechanic? Or any other suggestions to help stop the engine thudding?

Quick fix solution: go back to using regular unleaded when i need to fill up again?!

Cheers :woot:

[NickS]

Today my engine hesitated a couple of times upon accelerating (revs went funny), however no 'check engine lights' came on etc. I also felt a slight thudding, through the seat, somewhere in my car.

Could be a dud lead ??? The fuel should be fine.

[markone2]

Driving on wet roads with TC left on ?......

[Arnott(VY)]

hasn't got traction control mate..

good thought though.

thanks

[VNV8]

i take it its an ecotec then? try switching back to ULP but i doubt it would help, the E10 should have a higher octane rating so should burn cleaner/smoother. have you replaced plugs, leads, or coil/s recently?

[Gozza]

Is it just dead or is it a sort of stutter under load? My ecotec does the same thing and has done for a while without any change in fuel. It's driving me insane - my guess is that it's either a plug or lead problem but I haven't had a chance to check it out.

[iamhappy46]

Also, check the crankshaft pulley rubber is not starting to crack. Common problem and can put the timing out via the crank angle sensor, which can cause momentary hesitations.

Fit a new fuel filter just in case. E10 can strip off the fuel varnish that builds up inside your fuel lines and clog your filter quite easily. Regualr use will dissolve it but may as well change the filter regardless of which fuel you stay on.

[Arnott(VY)]

have you replaced plugs, leads, or coil/s recently?

i rang my local mechanic, and he recond it was a sparky lead aswell.

i havent replaced them i quite some time. not actually sure if theyve ever been replaced.

do you know if a lead is very hard to replace myself?
im a real tightarse and prefer to do things myself whenever possible :eyes:

and yes its an ecotec not an alloytec :(


Is it just dead or is it a sort of stutter under load? My ecotec does the same thing and has done for a while without any change in fuel. It's driving me insane - my guess is that it's either a plug or lead problem but I haven't had a chance to check it out.
also gozza yeah it only happens when under load.

it only hesitates in the rev range of 1000 - 2000 (under load/acceleration), anywhere after that its fine.


Also, check the crankshaft pulley rubber is not starting to crack. Common problem and can put the timing out via the crank angle sensor, which can cause momentary hesitations.

Fit a new fuel filter just in case. E10 can strip off the fuel varnish that builds up inside your fuel lines and clog your filter quite easily. Regualr use will dissolve it but may as well change the filter regardless of which fuel you stay on.

iamhappy46,

what is envolved in changing a fuel filter?

[iamhappy46]

Buy a new set of leads from Repco/Bursons, etc. NGK make some good leads :)

Take off each old lead individually, fit the new lead of same size for each lead you take off before removing the next lead. Should have no problems this way.

Fuel filter is located above the right hand wheel under the car from memory(long time since I looked) and there is a recent guide on here for removing the fuel filter snap locks.

[Arnott(VY)]

mate you are a bloody champion!

thanks heaps for that,

also just one more thing, how much am i looking at paying for the NGK leads?

[iamhappy46]

Depends on who you know... Around $60~90 is reasonable as some stores can give better discounts if you know the right people.

[Arnott(VY)]

thats awesome,

do you recommend changing the sparkies too?

[jackdaniels3]

Hi All

I have a WH statesman with a 5.7lt gen3 engine. I recently had the air conditioning serviced and they replaced the BCM and air compressor.
When i picked the car up i noticed it was hesitating during acceleration.
I have replaced plugs, leads, pcv and pipe,injector seals,inlet manifold seal and mass air flow sensor.
It doesn't register any codes and i am lost ?
The car has injected gas and this fault is present with gas or petrol.
Any help would be greatly appreciated.

Thanks
Jack

[jackdaniels3]

Hi All

Chevy from Chev's Performance Centre fixed my problem.

It was a bad connector on the maf airflow meter. He was very helpful and really looked after me on price. If any one has a problem or needs work done go see them.

Thanks chev, a lot of people looked at it before you and couldn't fix it.1/2 hour later all fixed

[MadMo]

Yeps. Chev is the man. Keep an eye out for a post in a few weeks time with the big numbers he got me.