MK2 gti intermittent power loss

[courtz1976-2dr]

Hi there all,

I am hoping that you can help me (and stop the incessant nagging ) with the problem I am having

car:
90 mk gti 1.8 8v

The car will very occasionally lose power when driving, like a complete miss or no ignition issue. Usually returns to normal on acceleration but sometime causes a complete stop. Pull over try wiggling a few things and it seems to go again.(but nothing in particular seems to make a difference, it is more just the waiting that fixes it) It will then go again OK.

I have checked and double checked pretty much everything.

PLEASE throw all and any suggestions my way.

Things tried

new ht leads
coil from different vehicle
different complete dizzy
checked most earth points
fuel pump connections etc
vacuum hoses


HELP HELP HELP - save my relationship

Cheers

Courtz

[patanga]

No power issue

Have you checked the wiring at the back of the ignition switch?

[velly_16v_cab]

Have you checked the wiring at the back of the ignition switch?

ditto, i had this on the way to the nurburgring a few years ago.
ignition switch was broken

[h100vw]

Fuel pump and ECU relays are common intermittencies.

Gavin

[Golf Loon]

Also check the lift pump in the tank has the pickup line attached and the hose does not have a split in it.

[courtz1976-2dr]

Have you checked the wiring at the back of the ignition switch?

ditto, i had this on the way to the nurburgring a few years ago.
ignition switch was broken

Fuel pump and ECU relays are common intermittencies.

Gavin

Also check the lift pump in the tank has the pickup line attached and the hose does not have a split in it.

Ok first of thanks for the replies - I have busy with work and havent had a chance to check back.

The other day I checked the wiring at the back of the ignition switch and the ignition switch itself and seems ok, I bashed and banged it to simulate driving over bumps (this is the time that it seems to happen but might be more a coincidence) but all seems OK I poked pushed and prodded the connections and no miss.

i did the same with the ecu and fuel pump relays - is it possible that they overheat and not close the contacts as reliably??? whilst I was there I checked the wiring to the back of the fuse box and wiggled each individually ( which was painful) and again no miss.

The fuel lift pump hmmm will have to look at this and let you know, would it get more likely at different fuel tank tank levels ???ie running low on fuel or full tank???

I am willing to try anything - any possibility that its the ECu itself or the ignition module on top???

Thanks and will keep you posted.

Cheers and Regards,
CourtZ

[courtz1976-2dr]

OK checked out the pump and hoses, seems ok... I can plug the end of the pump and blow into the outlet with no air escaping. The contact seemed dirty so I cleaned them up whilst having the pump out.

I am taking the car on a longer trip tomorrow and see how things go. It seems that a longer trip brings out the worst with this problem.

So yes I am still copping abuse fingers crossed I wont have troubles tomorrow.

Cheers for all suggestions, if there are any other things however obscure they may seem please tell me.

Courtz

[joshyd-mk2gti]

The fuel lift pump hmmm will have to look at this and let you know, would it get more likely at different fuel tank tank levels ???ie running low on fuel or full tank???

before i replaced my transfer pump, the car would hesitate/surge when the tank was less than 1/4 full. it would get worse when the tank got lower, especially when accelerating. it only stalled once or twice, i guess the main pump still has enough kick to keep it going.

[benough]

Was there any resolution on this?

We've just developed the same issue

[h100vw]

Was there any resolution on this?

We've just developed the same issue

If it seems totally random, varying run times before failure.

The 2 cleanest things to look at have to be the ECU and fuel pumps relays. I have seen plenty with dry soldered joints in them. All you have to do is take the lid off the relay and have a look for dull grey solder. Anything that is shiny is usually pretty good.

If you have dull ones, grab the blade and wobble it. If you can see the solder side moving, bingo, bad joint. Grab a soldering iron and get the old solder off. Heat the solder up and tap the relay on something before it cools and the solder will fall off.

To re-solder the joint you need some flux really as there's not usually enough in modern solder. Make sure you get the joint good and hot then feed in the solder. Being careful not to move the blade while the solder cools.

Repeat on all dodgy joints.

The ignition switch could be another one.

Does it just die completely or does it just feel under-powered?

Gavin

[benough]

Well it dies but only in splutters, but it does stall sometimes.

It's off to VW Village this morning (brother's in town) so I'll try to arm him with all this knowledge.

[Depone]

Was about to start my own thread about this a while ago...However I thought the issue had been resolved, but it has started up again.

My car is 85 GL 1.8L

The problem starts when the car is under or around half a tank. It splutters/loses power then eventually stalls, usually on the most convenient spots like Punt Rd

After banging the fuel tank and turning it over, the car starts fine then I fill it up with fuel and it will be ok again.

I have had my car at very well known VW mechanics in Melbourne twice now with this and they can't seem to find the issue with it, as it usually runs fine ( especially at there )

They say they have tested all the electrics, relays and fuses and apparently taken the fuel pump out of the tank and checked it. ( looking back now after learning there is a entry point in the boot, I can't see how they took the lift pump out because you have to move sub/amp and I would of known )

I have been told by them that as it seems the lift pump in the tank is in working order, it is the outer "main" pump that could be the issue....BUT that they are no longer made/very hard to get costing $700+.

It had been a while since the car has had this issue since it's last trip to the shop ( $1400 later )....So I had left it at that.

Now after it playing up this weekend I decided to put more effort into finding out more about these "rare" main fuel pumps and try to purchase a new lift pump.

Can anyone help me out with part numbers here?

I have found these...Am I right in saying the "in line" pumps are outside of the tank?

1985-1986, 1988-1992 Volkswagen Golf Electric Fuel Pump - 152-0772 Beck Arnley - Fuel Delivery 85-86, 88-92 Golf Electric Fuel Pump - PartsGeek.com

152-0811 Fuel Pump Volkswagon Jetta Golf GL1.8L 1780CC GAS in line New Old Stock | eBay

There is also a bunch on here...In tank & in line.

Fuel Pump - Auto Parts Warehouse

Any help would be much appreciated.

[h100vw]

Give us some more information on your car mate. I am not aware of an injected GL so my first instinct is to call BS on the fuel pump scenario. Unless you can state the car has Kjet injection.

Gavin

Was about to start my own thread about this a while ago...However I thought the issue had been resolved, but it has started up again.

My car is 85 GL 1.8L

The problem starts when the car is under or around half a tank. It splutters/loses power then eventually stalls, usually on the most convenient spots like Punt Rd

After banging the fuel tank and turning it over, the car starts fine then I fill it up with fuel and it will be ok again.

I have had my car at very well known VW mechanics in Melbourne twice now with this and they can't seem to find the issue with it, as it usually runs fine ( especially at there )

They say they have tested all the electrics, relays and fuses and apparently taken the fuel pump out of the tank and checked it. ( looking back now after learning there is a entry point in the boot, I can't see how they took the lift pump out because you have to move sub/amp and I would of known )

I have been told by them that as it seems the lift pump in the tank is in working order, it is the outer "main" pump that could be the issue....BUT that they are no longer made/very hard to get costing $700+.

It had been a while since the car has had this issue since it's last trip to the shop ( $1400 later )....So I had left it at that.

Now after it playing up this weekend I decided to put more effort into finding out more about these "rare" main fuel pumps and try to purchase a new lift pump.

Can anyone help me out with part numbers here?

I have found these...Am I right in saying the "in line" pumps are outside of the tank?

1985-1986, 1988-1992 Volkswagen Golf Electric Fuel Pump - 152-0772 Beck Arnley - Fuel Delivery 85-86, 88-92 Golf Electric Fuel Pump - PartsGeek.com

152-0811 Fuel Pump Volkswagon Jetta Golf GL1.8L 1780CC GAS in line New Old Stock | eBay

There is also a bunch on here...In tank & in line.

Fuel Pump - Auto Parts Warehouse

Any help would be much appreciated.

[Depone]

Give us some more information on your car mate. I am not aware of an injected GL so my first instinct is to call BS on the fuel pump scenario. Unless you can state the car has Kjet injection.

Gavin

Sorry it's a South African import 85 GL 1.8, it is a K-Jet engine.

[h100vw]

Sorry it's a South African import 85 GL 1.8, it is a K-Jet engine.

That's ok mate, needed that snippet to get further.

Hopefully, you are a bit handy diy on the car.

Best thing you can do is get yourself a MK2 Golf Haynes manual. In the fuel section it details how to check the pump flow/volume.

Essentially, you jumper the fuel pump relay and disconnect the return pipe and see how much fuel comes through in a set time. That should give you a good idea about the state of the pump.

If it is under performing there, then there's a case for getting a new pump.

Does the standard pump whine loudly? They can be quite noisy when OK but get bad before they quit altogether.

A lift pump would be worth fitting assuming the main pumps are hard to get. I doubt they are though, not with the internet and the massive number of Kjet VWs in America.

I'd want to do the volume check first though and a pressure test as well. The gauges are pretty checp to buy online too.

Gavin