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Discussion Starter · #1 ·
Hi all, my 2.5 aaf engine is driving me crazy!!
It doesnt seem to want to rev past 2000rpm in any gear when its warmed up a little. Replaced the coil and it was fine for 2 weeks.
I have litterally replaced all sensors and the exhaust since christmas.
Thought it might be a head gasket problem but had tested today and its fine, had a compression test and all cylinders where 180psi.
It never shows up any fault code.
Has anyone got any ideas?? Only other thing I think it can be is the ecu. Does anyone have a spare they are willing to sell me??
 

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one of mine is a 2.5 petrol. I had similar problems and no fault codes stored. although it was due a service so I did all the usual plugs leads cap and arm stuff etc. I rebuilt the dizzy with a new hall sender and replaced the coil too. It did run a little better, but still not cured the main problem of not being able to run above 2k. then I remembered a similar problem I had with a Nissan 200sx a few years ago, where sometimes it would rev on boost, and sometimes not etc. that turned out to be the standard fuel pump not able to cope with the power of the engine. I replaced the fuel pump with an uprated one on the Nissan....this totally cured it and it flew after that.

so I shopped around online and tried all the various suppliers for the intank fuel pump for my bus. I finally got the price down to about £30 or something from eurocarparts. ( some quote well over £100 for the same part!!) take yours out complete and upto your local euro to get them to match it up, because the one they gave me was slightly different too mine as the one in there listing . so you need to get it matched up visually. this one was also cheaper than the one they listed for it too A:
it was a bit of a fiddly and messy job, to get it all done, but it made the world of difference, as it has never run so good A:T:

so I'm pretty sure that this is your problem too. if you need any more imfo give me a shout. In fact i'll go and find the receipt now and get you then part number you'll need. :ILU:
 

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Discussion Starter · #3 ·
Cheers for the reply fella, Heritage do one for about £30 to, its the same pump as a mk3 8v golf. Tps guy told me that.
problem is, now and again it will run fine and as I say when cold it runs fine.
I have had pump out and tested it, appeared to run great.
I may as well change it and try though ive changed everything else..........
 

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mine was the earlier model as it's a j-reg. so the part number for was 441440481. if you use euro.( this will only cover upto about '92.) this only cost me £23.94 inc vat ( trade price)

if yours is later than this, you'll need the other one although they still do it, but it was a bit more money, I think that's the one that was about £30, which is still cheap T:

before I leave it with you, when you do the job make sure you mark up the the top part of the pump housing and the tank, with alignment marks,use a pen or scriber so that you fit the new one in the same position. take some pics on ya phone too. also make sure the pump is fully pushed down into the tank onto the rubber seal, before you try to align it. you'll also have to swap over the fuel sender unit onto the new pump. these are very delicate so go easy with it.

good luck then mate T:
 

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I had my pump out and tried it too, but it only lost pressure again when all connected back into the tank. even at 2k revs, you'll still get enough psi to get plenty of fuel out visually.

I'd change it mate for the money T:
 

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Discussion Starter · #6 ·
Cheers pal, will look at euro as just looked again on heritage and they want £50....
Gonna be a week or two as im busy with work but will let you know how I get on.
 

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Discussion Starter · #7 ·
Been doing a bit of testing today. When cranking the engine over I'm only getting 10.48 volts at the fuel pump (battery is fully charged) is this correct??
 

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Discussion Starter · #8 ·
I appear to have fixed it! While poking around found I was only getting 10.4v to the pump. Bridged the relay and got 12v to the pump. So replaced the relay, all good.
I also noticed the pump wasn't self priming. So while switching the ignition on I flicked relay 30 and the pump would self prime. Replaced relay 30 and all appears to be good. Everyone says just feel the relays and if they click they are good, mine clicked fine, but they where not working correctly.
 
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