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Discussion Starter · #1 ·
Hi

Dunno if anyone else has read some previous posts on the problems with my car but heres a new outline and some updates. Basically the problem is the car loosing boost and the car becoming undrivable over 80 mph with the boost guage rocking backwards and forwards. After further investigations the garage tell me the timing is all over the place for the car too causing occasional small misfires and more severe ones at high revs and speed.

So far the garage have tried the following with no sucess:

1. All turbo pipes check and replaced

2. MAF Tested also tested with alternative MAF

3. N75 valve uprated

4. Samco TIP installed

5. Turbo uprated to Ko3s

6. Intercooler Checked

7. Manifold Checked and modded

8. Crankshaft sensor replaced (i think thats the sensor)

9 . Loads and loads of other parts checked

10. Coil Packs tested and replaced

To date the garage have had it 3 weeks on the current stint and have it looked at by two diagnostic experts and the top techincal guy from the local VW dealership. All dont know what could be causing it.

The next thing the garage are going to do involves changing some part so my fuel pressure is higher up to 5 bar i belive he said feeding the engine more fuel.

At this moment in time the car seems totally unfixable just wanted to see what u guys think ?? I on the border line of ripping all my mods out and trading the car in for another 1.8t but id much rather have mine fixed.
 

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OldSkool Crew
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Try the fuel pump mate...

I've seen a couple of 1.8T's now with problems that have taken ages to diagnose that turned out to be the fuel pump.
 

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The MAP sensor basically tells your ecu what boost to provide the turbo with as far as i know, its a bosch made part that is bolted onto the side of the intercooler. I've been experinecing a sort of similar problem to yours and i've been advised its the map sensor or a sticky wastegate on the turbo.
 

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As Josh says sounds like a fuel pressure problem. When was diagnosed with a pressure gauge attached to the fuel pump and the car was put on the rolling road. The problem occured under boost when the fuel pressure should be the FPR rating + the boost being generated.
 

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I was just about to suggest the crank shaft sensor when i noticed you've already had it replaced!!

I'm going to put my car to a fuel injection specialist in the next few months hopefully as i think this is where my problem is coming from now.
 

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Take it to AMD and get them to diagnose it on their rolling road. My previously unfixable problem (many trips to VW) took about 40 minutes for them to cure. They are an order of magnitude better at diagnosing engine faults than VW technicians.

Ben
 

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Discussion Starter · #16 ·
Its with my revo dealer at the moment where are AMD ?? nowhere round here i bet. Just had the CAT checked no problem there waiting to hear back today about the fuel pressure regulator being put on.

Also the garage say they dont think there is anthing wrong with the fuel pump as the pressue has been motiored and its not fluctuating.

Do AMD have a web site so i can contact them direct ???
 

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Discussion Starter · #18 ·
Do any of these guys have web sites or emails so i can contact them about my problem and see if they have any fresh ideas ??
 

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JBS were the ones who diagnosed my fuel pump fault on there RR, they charge ?45 an hour for RR diagnostic. I'd recommend calling them on 01246 550400.
 
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