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gravitationally challenged

vsMick

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this happened a few weeks ago on one of those really hot days. We were driving to a mates place and on the way there were many steep slopes. It was hot so we had the air conditioner on.

It was stop start traffic and on every slope where i had to put the foot down to get the car moving the car would jerk a lot. Its hard to explain, it feels like the cars "missing" as a friend put it. Its feels like when you drive over small holes that make the car jerk, except its the car doing the jerking on a perfectly smooth road. Some of the jerks are very "violent" while others are hard to tell if its the car or the road.

I atributed this to the hot weather because it was fine up until that day (first really hot day of the year).

However we were driving last night and it was reasonably cold and the car was doing the same thing. The friend i had in the car with me at this time said that if it was doing it all the time he would say it was the head gasket, except it only does it on a slope (that might describe the feeling a bit better).

Driving up a slope normally and the car is fine, its only when i have to put my foot down to maintain or increase speed that it jerks.

A week ago the original friend who was with me had his fuel pump die on his ford EB and he said it was the exact same feeling (the jerking) just before his pump died.

The car was fully serviced (filter, fluid changes etc etc) two months ago.

So what do you think????

fuel pump
filters
injectors

???? we have not the slightest idea????

perhaps it may be worth checking the ecu for any logged errors???

apart from checking that im not sure what to do. The worst thing is thats its very random, it seems to jerk consistantly on every hill until the car gets very warm, then after that it only does it occasionally.

im worried if i take it to holden they wont find anything because it dosent decide to do it that day. not sure. Also were putting in splits so the cars kinda in peices (dash and door panels, but its been fine like this for a while)

any random ideas as to the problem would be great, or any one whos had a very similar problem.

im inclined to think it may be the fuel pump because its got to work alot harder when going up hill but experience tells me it could be just about anything.

sorry for the long post but i wanted to describe everything as best i could

cheers
 

syndosis

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Hello
I am no expert and if there are experts out there that think my idea sucks, thats cool, just advise this guy as best you can.
If it is only doing it on a slope then the amount of fuel in your tank could cause this problem, slope means a low fuel level angles it away from where fuel is pumped from to the engine, thus the splutter if its not getting much fuel until you level the car up a bit. Happens to my vr everytime I let fuel lvl get too low.. nearlly didn't get to a petrol station once as was on a hill...

apart from that, finding the logged errors is the best bet and report back to this forum so they have more of an idea of what the car thinks is wrong..

just my 2c worth
Cheers
 

vsMick

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haha yeah that had also crossed my mind. Only problem is that i get quit a bit of free fuel and cant really remember when i had less then half a tank in there. My tanks probably three-quaters full on average.

I'll check if ive got any logged errors then, might have to wait until next week to do that though, damn exams and my lack of study

thx a lot
 

Jamie_87

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does it do it if u give the car a bit on a flat road too? If so it seems to be doing it under load, so maybe look at spark plugs, leads, injectors maybe?
 

holden007

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I reckon its something with the fuel, maybe the pickup in the tank is not right on the bottom??
 

Patrio7

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checked your transmission fluid?
 

vsMick

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ill check the transmission fluid tonight. Im pretty sure it was changed last service though.

i gave the car a bit on flat surfaces whenever i had the chance and no, not really. If it was doing it it was really hard to notice over bumps in the road. BEcause we also thought if its doing it because somethings loaded up to much it should do it also do it on flat surfaces, but apparently not really. Ill try and take it out tonight and give it another go.

ill talk to a friend tonight about new plug leads, see what he reakons (he has a much better idea then i do).

cheers, ill try and check everything sometime tonight and get back to you guys asap
 

kenwstr

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It's just typical missing.

You only really notice missing when under load, the more load, the more noticable the missing. It doesn't show up as much just under power on the flat unless you are towing something heavy. You get it more on hills because your loading the engine against the weight of the car.

Don't panic or look for serious and exotic causes. Missing is usually electrical. Check the ignition system, high resistance plug leads, plug gap and condition etc. Fuel problems tend to show up as general lack of power. Like low pressure, blocked filter etc. Even air in lines tends to run good a few seconds loose revs then good again, not jerky. I don't think it's fuel unless it's an injector.

I'm betting it's the leads though.

Ken
 

vsMick

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wow thanks thats a good answer.

if fuel problems show up as general lack of power its certainly not fuel then, the car seems to have developed more power over the last few weeks. Ive been driving it harder then usual and the car feels really good the next time I go for a drive. The guy i brought it off clearly granny footed it the whole time, it was very sluggish when i got it off him. My parents have the same car (96 VS) so its easy for me to compare.

Thanks, ill see what i can do and get back to ya's

p.s: for the record this car has had so many electrical problems im not going to be surprised by any more of them, so you may be right.
 
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