stuart8425

New Member
Hi everyone. Ive recently got a p38a 1997 diesel auto which stalls when changing from park to drive or reverse and vice versa and ocaisonally when slowing for junctions. I checked the fuel system for leaks, splits etc. changed the diesel filter and there is plenty of pressure from the in line fuel pump. I had some diagnostics done (snap on reader) suggested map sensor. Changed map sensor for new one and problem remains. Has any one got any ideas as when it runs there is plenty of power and changes gear well. Thanks Stuart
 
Get some proper daig on it MAP sensor cannot cause that. Proper diagnostics would probably tell you there is a fuel quantity control fault. Track or wiper on fuel quantity feedback pot wears causing this. Only cure is to have your injection pump refurbished or fit an exchange injection pump. Can sometimes be held at bay for a while by increasing idle speed with diag to about 850-900 RPM. But if you do that don't leave the car idling in gear at lights Etc.
 
Bit of a red herring that one Keith. It's the fuel not being increased to take the load that causes the stall.
You may well be right, but I had an old auto that did that (petrol), removing the ancient gunk that served for ATF flushing and refilling cured the problem.
It also cured the hard shifts.
 
You may well be right, but I had an old auto that did that (petrol), removing the ancient gunk that served for ATF flushing and refilling cured the problem.
It also cured the hard shifts.

Well yes, fluid the consistency of mud in the box would cause the torque converter to overload the engine, if it did not have idle control it would stall. But in this case RPM drop should be detected and fuel increased to take the added load. Odds on a quantity control servo problem. :);)
 
Hi guys thanks for the advice. I was hoping it wasnt the fuel pump but something simpler. (by that I mean less expensive) The auto box is very smooth and changes up and down. I might try increasing the revs or if not sell it as a rolling project. Thanks once again.
 
Hi everyone. Just an update and a query. I put it in to a garage who fitted a used fip, The rr started and ran well for about 15 mins then died. After about a two weeks they said the pump must have been faulty. They then fitted another now rr starts and revs but refuses to idle and just dies. They say that there is 8 degrees of timing adjustment and manifold needs to be stripped off on each adjustment. Does this sound right?

Stuart
 
Hi everyone. Just an update and a query. I put it in to a garage who fitted a used fip, The rr started and ran well for about 15 mins then died. After about a two weeks they said the pump must have been faulty. They then fitted another now rr starts and revs but refuses to idle and just dies. They say that there is 8 degrees of timing adjustment and manifold needs to be stripped off on each adjustment. Does this sound right?

Stuart
No, timing is set exactly with a dial gauge and some other bits. Wammers knows all the in's and out's of the timing.
Garage do not know what they are doing.
 
Hi everyone. Just an update and a query. I put it in to a garage who fitted a used fip, The rr started and ran well for about 15 mins then died. After about a two weeks they said the pump must have been faulty. They then fitted another now rr starts and revs but refuses to idle and just dies. They say that there is 8 degrees of timing adjustment and manifold needs to be stripped off on each adjustment. Does this sound right?

Stuart

No, static timing is done with special tools to thousandths of an inch. Have they been playing with the pumps and gotten the tops in the wrong place? Needs to be put on proper diagnostics and any faults read. More than likely fuel quantity servo problem.
 
Yes I believe the pumps and tops have been swapped about. Is it possible to start from scratch and time it back up?

Positioning of mid section of pump is critical, you cannot just remove and refit anywhere. That is more than likely the problem. Fore and aft movement of the mid section alters fuelling and MUST be set correctly. This can be done using good diagnostics which emulate the test rig the pump is set up on at the factory. But it needs to be done by someone who knows what they are doing. Obviously your garage don't. Timing is a totally separate function and will not give you what you have if out slightly.
 
Setting the idle fuel by tapping the mid section fore or aft after the mid section has been removed and refitted can be a long drawn out exercise. It needs to be tapped fore or aft until you get as near as possible a rock steady 750 RPM idle. Then rev the engine slightly beyond the 9% point where the idle switch is engaged and let revs drop. If idle revs drop to just above 750 then settles back to 750 it has slightly to much idle fuel. If the revs drop to just below 750 then rise to 750 it has to little idle fuel. Keep adjusting either way until when engine is revved idle drops back to exactly 750 RPM. Of course it is far easier to do electronically on the pump calibration rig. :D:D
 
Hi Wammers this sounds like what theyve been doing. Just been in and theyve had it running at a 1000 revs but it has now thrown a glow plug out and they think part is is still in the cylinder. :eek:
 

Similar threads