Fuel pressure? Electrical?

Carbs; K-jet; Tanks; Lines; Filler necks, Senders; aftermarket fuel systems; Exhausts and Manifolds;air filters - standard and aftermarket
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brucegtx
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Fuel pressure? Electrical?

Post by brucegtx »

I'm now really beginning to lose the will! I've now had my mk2 monza for 3 years and still done less than 50 miles in it. It had an unknown fuel issue when purchased but I've now systematically gone through most fixes. It runs fine for a couple of minutes until and then cuts out you start it again and it's fine for another couple of minutes then stops again. It will drive but chugs after a couple of minutes, turn the key for a second and start it again and off she goes again. If you rev hard it splutters on hi revs.
List of things done. New fuel pump, tank, filler neck, lift pump, ignition module, fuel filter, aux air valve, inj sealsfuel pipes. Checked coil and ok. When you disconnect all electrical support such as cold start ect still does same. The only thing I've not changed is accumulator but they don't go wrong apparently?
The cars mint, I just want to drive it but everything I do it fails. Oh and fuel cap.
Please, is there an answer out there??
I posted pics on Facebook the other day thinking a new tank and filler would do it. Not!


mr.brown
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Re: Fuel pressure? Electrical?

Post by mr.brown »

The first thing I would check is fuel pressure and flow. There are pressure test kits on ebay. Is there fuel getting through to the metering head? Is there fuel getting to the injectors?

You may have changed the fuel tank/neck/pumps but did you check/change the plastic reservoir on the side of the tank? There's a filter in that too. And the metal S bend pipe between that and the lift pump?


Tim_R
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Re: Fuel pressure? Electrical?

Post by Tim_R »

Have there been any checks on the metering head to make sure that isn't partially clogged up? I'd need to check my K jet documentation to be sure but I think there is a gauze filter in the banjo fitting from the filter to the metering head. Would be worth checking that is clear as it sounds like a fuel starvation issue. Whereabouts are you based?


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brucegtx
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Re: Fuel pressure? Electrical?

Post by brucegtx »

Thanks guys, will look into both. I'm in mansfield I notts. Put her back to bed for a few days. A agh!


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scrappy1382
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Re: Fuel pressure? Electrical?

Post by scrappy1382 »

have you checked the voltage supply to the main fuel pump ? ( under the car ) , mine done almost the same as yours is doing and found alternator giving out 13.8v and main fuel pump only getting 10.6volts ... so after idling or even driving , it would cut out. since doing a direct feed from battery , then relayed to main feed to pump it was getting the same voltage and hasnt let me down since. a the main pump gives out a nice healthy buzzing sound now :-D its a simple 5 minute test using a voltmeter ! try it first before you mess with the k jet system bud, see how you get on . if you would like pics of how i done mine, then pm me ya number and ill send you some ;-)


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brucegtx
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Re: Fuel pressure? Electrical?

Post by brucegtx »

Thanks Shane, will check that out. Got it driving now and fine for a little while then becomes really lumpy spluttering and when you ask anything of it it's splutters. If you flip the key off for a split second off she goes again for a little while. It's as if when you turn the key it resets something for a short time. At least i can drive it gently (very) now and maybe get to the bottom of it.


duggers
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Re: Fuel pressure? Electrical?

Post by duggers »

Have you checked the fuel pump relay? I didn't see that on the list.
I know it sound odd but if its old they can do some very odd things. You can bridge the contacts to temporarily run without the relay or just get a known good one to substitute it.

The symptoms are the same as rust in the system from when the filler neck or fuel tank get corroded and start dumping crud in the system. I had this with mine and the first time it happened i was going for a rather spectacular overtake......
Not saying it is rust but everything points to fuel delivery being restricted. As Tim_R says there is a gauze filter at the banjo for fuel supply to the metering head.
Also have a look under the car at the fuel lines and make sure they haven't taken a good whack somewhere and been partially crushed which could restrict flow.

All the above are straightforward and quick checks.

Good luck!


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GT Matt
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Re: Fuel pressure? Electrical?

Post by GT Matt »

Bruce, I'm in Derby if you want any help? My diary is quite full but I'm sure I could squeeze you in somewhere.

Matt


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