Juddering Start

[JBOB 0]

Ive got a really annoying problem with my car (1.8 16v) When i pull away from standing it judders and jumps until i get the revs above 3.5K ish.

The only way i can describe it is like when you pump the gas pedal really quick and it makes the car

kangaroo down the road :roll: It might just be me but it doesn’t seem to be as bad when i first set off from cold :roll:

 

Its only started in the last couple of days and the car pulls/drives really well after its had its little starting fit :lol:

I haven’t had chance to have a look at it but to be honest i don’t know where to start........that’s why im writing this :wink:

This is making my car really horrible to drive and it feels like its getting worse -- help please !!! :D

[stevemac 0]

I had a similar problem on my old Scirocco (similar injection system). Turned out to be a sticking valve in the fuel distributor. If your car starts to develop a misfire at low revs - chances are you may have the same problem.

 

If it's not that, I'd be checking the fuel pump relay too. When they start to go, they often give symptoms as you describe.

[JBOB 0]

Thanks Steve, I cant tell if theres a misfire as im to busy trying to keep the car going at low revs.........but im nearly sure there isnt one (fingers crossed)

 

Do you think i should change the relay anyway???? and which relay is it please so i can get a new one.

Also are they expensive (Im skint LOL)

[JBOB 0]

Just found this on GSF is it the right one ??

 

93593 FUEL INJECTION PUMP RELAY CO 9/88 > 7.50

[stevemac 0]

Looks like the one to me - at that price, I'd change it anyway even if only to eliminate that from the possibilities.

 

If the relay cures your problem - the real problem will be the internal fuel pump in your petrol tank. It's quite common for these pumps to fail. This causes extra strain on the external fuel pump & the relay needs to draw more current - this is why the relay will have begun to burn out. In a nutshell - if the relay cures the problem, change the internal fuel pump as well or the new relay will soon also burn out.

[JBOB 0]

Cheers Geezer :D

[JBOB 0]

I decided to pop into my local dealers to see how much the relay would be from them...........I found out why their called Stealers £29.00 + VAT :shock:

So i went to GSF and got the exact same relay (except for the VW markings) for 7.50 + VAT :D

 

Fitted it and there does seem to be an improvement........as in its not as bad and sometimes there’s no judders at all :D

 

So do you think i should get a new internal fuel pump......Is that the problem :roll:

[Walesy 0]

will it sound stupid asking if it could be your clutch going?

[JBOB 0]

It doesnt feel like a clutch slip. Its just jolting like its running out of fuel, which cant be cos ive never got less than 1/2 a tank and ive got a full tank at the min :roll:

[stevemac 0]

JBOB, from what you say, I would be 95% certain that your internal fuel pump is completely dead. I think we sell them for about £20'ish. Fairly easy to fit, it fastens to the fuel level sensor in the tank. Access hole is under the rear seat base. You may need 3 x "OOO" size steel jubilee clips to re-attach the fuel pipes - you'll see what I mean when you lift the rear seat base.

 

 

Here it is -

18389 FUEL PUMP-IN TANK CO 16V 9/88 > £19.95 + vat

 

Change this as soon as possible & you may also need another new relay - your current relay will only last a few miles with the increased amount of amps put through it, caused by this dead pump.

[JBOB 0]

Ive HAD to do a 350 mile round trip in my car today and was fine at first but when i came off the motorway it was juddering so bad that i felt like walking (very unlike me) so it does sound like the pump has gone :roll:

 

I dont get paid til Friday so my g/f is gonna take me to work this week :( and ill fit a new pump on Saturday :D

 

Thanks Steve :D

[stevemac 0]

No worries m8 - internal pump failure is quite a common problem with K-Jetronic injection.

 

Hope you get it sorted .. :wink:

[JBOB 0]

I got the G/F to drive over to Bradford today while I was at work and pick up a new pump :D

 

Only took 20min to fit and the car runs fine now. Funny how you don’t drive your car for only a couple of days

and then you miss it :lol:

 

Great diagnosis Dr Steve, Thanks mate :D :D

[stevemac 0]

No worries J - glad you got it sorted m8 .. 8)

[Walesy 0]

my 16v's juddering...and its lacking in power.....i've only just bought it and the guy i bought it from said hes had engine mounts recently.....does the lacking in power sound conducive with internal fuel pump failure?

[stevemac 0]

Could be - get a relay & see if your problems stop. They're cheap enough, even if it's only to eliminate it from your possible causes

[Walesy 0]

ta!

[Walesy 0]

anyone know which relay it is/?? :oops:

[Walesy 0]

no-one? :(

[Supercharged 2]

67

[Supercharged 2]

67

[Walesy 0]

:D ...you're a gent.... :D

[JBOB 0]

:( :( :( :(

 

Its doing it again :( :( Can i assume that ive ****ed the new relay as id done about 350 miles before id changed the pump. Its just as bad as before and making driving across town to/from work very embarrassing not to mention horrible to drive.

 

I don’t wanna go buying another relay without some pro advice........ :D

[JBOB 0]

This has now gotten to the point where if i try to pull away there are no revs for about 5secs, and then i go flying down the road juddering til the revs reaches about 3.5k. So basically its getting a lot worse.......

[Bobby 0]

as stevemac suggested it definitley sounds like a fueling problem i would suggest to try change the fuel pressure regulator on the rh side of the head.