mk4 astra 1.7td idle problem......

[rc]

ok, bit of a story to this one. ive got a white mk4 astra van 1.7 gm td, driving along oil pump went and threw a rod through the block. was all fine before the mechinical fault. so towd home dead.

next i bought another mk4 astra 1.7 gm td red van, identical, which was spares and repair as it had the enitival diesel pump ecu death. so got the new one home to use as a donor. before removing the engine i decided i wanted to get it running in the red van just to check its ok. so fitted my ecu that i knew was good and brooom fired up. ran fine and took it for a test drive and pulled perfectly and well, no hesitation. the problem is when it drops to idle it goes all lumpy, like its only running on two. give it a blip and no hesitation just fires straight away, hold it at 1500rpm and it idles perfect, drop it down onto tickover and its back to major lumpyness.

so went with it thinking it might be a dicky throttle pedal or something and dropped the whole lot complete on the subframe and fitted it all into the white van. fired up first time but the same, rough as guts idle. anywhere else in the rev range and its perfect.

googled it and poor idle came up with egr valve. so took the whole egr system off the old engine, cleaned and fitted, still the same, tried the afm from the origional engine too, still the same, checked for air leaks with wd40 and an airline, couldnt find anything.

cracked off the injectors while running over and over again just to see if there is some air in there, and it seems there isnt fuel coming through on idle. defo on cyl 1 and 4 anyway, but pours out when reved. the other thing ive noticed is when on idle and bouncing around the speedo fluctuates between 3 and 5mph, rev it and it drops down to 0mph again. just running the water up to temp on idle id aparently traveled 0.4miles??

there is no em light or fault codes.

help me!

[rc]

things it cant be are throttle pedal, tank or lines, wiring looms, main ecu, as they all stay with each van. i also fitted new oil, diesel and air filters...

what controls the idle and can you adjust it??

[paul.spencer]

Faulty crankshaft sensor or connection maybe? I guess you have a known working sensor on your original van - pop that in and see if it makes any difference.

(Hey I re-read your post a couple of times but its a bit unclear to me - I assume that you installed your original injector pump on the red van - is that correct?)

[rc]

i,ll try a crank sensor just so we can rule that out too.

its the origional pump out of the red one still on its engine, i just swapped the ecu on the top.

[paul.spencer]

OK I think I get it - you mean you replaced the injector pump EDC in the red van pump with the one from the other pump? I think it would probably have been better to replace the entire pump. Thing is, as you can imagine there's internal stuff that fails on those VP29 pumps that you just can't get to. If you replace only the EDC then its only partly repaired.

We had a lengthy thread on failure of this pump on another forum. It involved blown EDC components as well as failure the equivalent of the stop solenoid inside the pump. EDC was repaired but the solenoid is both inaccessible and apparently unavailable. Anyway, I think you may have to replace the red van pump with the other that you knew worked and reinstall its original EDC unit.

[rc]

hmmm that did cross my mind. timing looks an apsolute bastard when changing the pump thats why i tried leaving it in there, is it really as bad as it looks with dti's and locking pins and the rest of it?

[paul.spencer]

LOL - timing on your MK4 X17DTL pump is a breeze compared with my MK3 just a few years earlier. Timing and fueling is all electronically controlled so all you need to do is use a locking pin or just a suitable sized bolt to lock the injector pump pulley.

The fiddly bit with my MK3 and its mechanical VE injector pump is that any time the cambelt is removed and reinstalled one is supposed to conduct "start of fuel feed adjustment" requiring a dial gauge adpater to pump, dial gauge, and fussing with the pump pulley - here's a couple pics

[rc]

so time the engine up to tdc, put a pin in the diesel pump, whip the belt off, take the diesel pump vernier pulley off and take the pump off? do i take the pulley off with the main centre bolt so not to mess with the adjustment? and keep the pulley with its origional engine?

thanks you're being a great help.

[paul.spencer]

I remember asking about this a while back - I think the pulley goes on only one way, or with a woodruff key or something like that but I would just be going by info in my old copy of TIS I got from somebody on one of these forums.

Tell you what, I just sent you a test email using email function on this forum. Reply to that so I know your email address and I can send you info as jpg attachments from my copy of TIS.

Cheers, Paul

p.s. just looked through the info and it looks like you undo the 3 smaller bolts but I'll send a 2 pages of info if you want it - the 3 bolt or assymetrically positioned so I guess that means the pulley can only go on one way really...

p.p.s. a mate of mine in the UK also has the MK4 X17DTL and I remember he sent a few pics of locking things up to do his cambelt job. I think he found that a medium length socket extension worked perfectly as a locking pin. Draper 52578 locking plate is handy for holding the camshaft at TDC...

[rc]

info received cheers mate. looks easy enough to do. i'll just have to make sure i mark up where the 3bolts came from on the pulley and match them up again so i dont have to go through the throuble of dialing in the cam etc when refitting the belt. should be pretty straight forward, would of been loads easier to do when i had the engine out of the car though

[paul.spencer]

Lock the flywheel at TDC with a genuine type locking pin on a spring (or Haynes says a bolt ground to a point). See if you can borrow a Draper 52578 plate (or similar Laser or Sealey tool) for the end of the camshaft. I had one sent from the UK. Holds it at TDC and keeps it there while you install the camshaft bolt (~75Nm + 60 degrees), which is bloody difficult to counterhold by hand. It gets around the need for a dial gauge etc. Lock each pump at TDC using a bolt (or the mid-size socket wrench extension if it'll fit) before removing the pulley. Tehcnically should be a simple enough swap if they are both at TDC - but I've only ever seen pictures never had my hands on one!

Keep us updated....

[rc]

changed the pump today, alot easier than expected, and all sorteded and sweet, horrray

thanks for the help and info

[paul.spencer]

Hey that's great news - done so quickly and all sorted too. Good work.

And thanks for the update - so often we're just left wondering what ever happened.

Cheers, Paul