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Intermittant Bog-down / miss - New fuel pump already tried.

7K views 14 replies 7 participants last post by  jonesin 
#1 ·
Hey guys...

it's been a while, but i'm back with another issue....

Car's been bogging down heaps bad lately, but only intermittently and once it's warmed up. Hitting the throttle (either in gear, or free spinning, from idle - 2k rpm it seems to be choking, and then >2k rpm it's fine). If I drop it quite low in rpm, it seems to misfire, fart and carry on unhappily.

Fuel consumption is a bit worse than normal, but the really weird part is that when the car is mis-behaving, I can simply turn the key off, then back on and it runs perfectly for 5 mins or so. That's a good temporary fix, but not really a solution.

When it's playing up, it will quite often stall (instead of idling), and make me look like a dick at the lights / in a carpark.

I've read through the bogging down thread, and yesterday threw in a new fuel filter and fuel pump. Whilst that has made the car feel awesome, the problem still remains (and is still able to be masked by turning it off then back on.)

so... any hints? I'm not sure what to try next... help ultra appreciated
 
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#3 ·
Cheers for the reply.

I threw in a new set of NGK's today but no better. Battery tests up good, and Alternator throwing out a solid 14V.

Next up i'm thinking injectors, or possibly ECU?
 
#7 ·
Thanks all,

Tried the reset while I was doing the plugs, no luck.
I spent a while chasing down a hissing noise about a year ago, but it never amounted to anything, however maybe this is what it was hiding all along. Admittedly it sounds really dumb to not have looked at this first, but I spent days looking for it last time (along with my mech) and we decided that it was nothing.

As for fault codes, I've got OBD2 and no scanner.

I guess tomorrow night i'll go hunting the hiss again...

thanks again everyone
 
#9 ·
Try spraying a bit of brake cleaner where you think the vac leak is. Once the cleaner hits the leak your engine will rev up. Also check on the underside of the air intake I had a leak there one time. The only reason why I found it was because I used the brake cleaner method. Be careful where you spray and be conservative. Keep us posted. :)
 
#12 ·
Free? Nothing down here is free! Registration alone is $770 for 12 months down here!

Nah, i'm good friends with my mechanic, it's just that he's on the other side of the city to me. I'll have a spray with some brake cleaner tonight.

cheers!
 
#13 ·
So thanks again for your help guys. I took it in to the shop the other night and had it plugged in and got all the codes reset. Drove it for a few days, then plugged it in again...

Turns out it was the cam position sensor. Left it there for them to play with, and now it's fantastic!

Car's running the best it ever has since I owned it! So much happy!
 
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