Engine 850: B5234T/2.3/20v/T5: Starting issue

[bb54]

Originally Posted by Chris_Rogers

I think you had an answer to, why both signals?

I was there at the begining of the thread and have been saying it's EMI all along. I don't think my suggestion to clean the starter motor commutator and brushes was followed, I suspect this is the source of the EMI. Poor connections and/or damaged wiring, during the engine change, may also be the case.

To really find the answer to the problem, a break out box for the ECU connections is required and a good quality 'scope. If these are available it should be relatively easy to discover the problem. As I suspect they are not then it becomes more a case of trial and error.

said bya wise man indeed, without the correct equipment it all becomes a game of chase the red herring.

its what the forum is about tho, if we all had enough cash to go main dealer, and leave it till they found the problem... half the forum would dissapear.

wayne

[stuartvolvo]

Hi all, sorry i havent been on for the last couple of days, i am sure you can all gess where ive been, (under the car). I took the inlet manifold off, battery, turbo hoses and the starter, to give me some more room. I then went and checked from the ecu sockets to every sensor in and around the engine, and had a good signal to everything, no broken or damaged wires. I also found that there was a bolt missing out of the starter motor, so i cleaned up all the metal work and made sure that all the bolts were tight, to make sure that everything is earthed well. Unfortunatley, the only thing that seems to have improved after i put everything back to gether is that the starter sounds healthier. I still have this starting issue, which seems to be more permenant than intermittant, although se does fire up straight away occasionaly.

If anybody has any other ideas, please be sure to let me know

Regards
Stuart

[stuartvolvo]

Hi all, as i said in my last post, i checked all the wiring in and around the engine and could not find anything wrong. I am now looking for a loan of a ecu, so that i can change them over and see if that makes a difference, just so i can take this out the equasion.

My ECU deteails are as follows.

Bosch A.52
PO1275003
IT2650000

If any body preferably local could help i would apprecaite it.
Kind Regards
Stuart

[DLM48]

Originally Posted by stuartvolvo

Hi all, as i said in my last post, i checked all the wiring in and around the engine and could not find anything wrong. I am now looking for a loan of a ecu, so that i can change them over and see if that makes a difference, just so i can take this out the equasion.

My ECU deteails are as follows.

Bosch A.52
PO1275003
IT2650000

If any body preferably local could help i would apprecaite it.
Kind Regards
Stuart

Sorry Stuart cant help your ECU is at least one up from mine with the imobiliser etc and i have a twin ECU set i think you might have only one - brain fade at the mo

i have a few Spare ECUS lying about

P09146371
1T22SO714

and
P09146476
1T28S2395

and of course the ones in the car which i assume/expect will be similar to the above

Hi Guys,

Just to let you know, my car is in the garage where the fault occured. (It is axactly as stuart is describing, doesn't matter if hot/cold etc)

Here is a summary of what has been done so far.

They have had it for 2 weeks now and have found that there is not always a spark from the coil.
I have had new ignition switch, rpm sensor, leads, plugs, dizzy cap and rotar arm, they have replaced ECU with 2 donor units etc still problem occurs, so unlikey ECU itself. They have checked the amp to coil, still probs.
Now they are checking signals from crank and cam sensors etc and I am waitin to hear from them.

My car was being remapped and was on the rolling road for a good 10hrs on the day the fault occured, now during these 10 hrs, the ECU was in and out of the car to tweak the map. Could this taking it out and putting it in cause a problem? I read that stuarts had a chip soldered in so may be similar problem somewhere?

Bison

[PNuT]

i would

push start the car under different conditions

i assume you have only pushed it with the ignition on?

i would try it whilst cranking the engine

& also in the cranking position with the starter disconected

[Mark_in_Conwy]

Originally Posted by stuartvolvo

Hi all, as i said in my last post, i checked all the wiring in and around the engine and could not find anything wrong. I am now looking for a loan of a ecu, so that i can change them over and see if that makes a difference, just so i can take this out the equasion.

My ECU deteails are as follows.

Bosch A.52
PO1275003
IT2650000

If any body preferably local could help i would apprecaite it.
Kind Regards
Stuart

Hi Stuart,

There is another number on the side of the ECU - mine is "0261 200 501 (549)". The numbers you specify are next to the bar codes on the end, and are different from mine. However, if the number on the side is the same, you're welcome to borrow my spare ECU (via jiffy-bag).

Although it is as well to check, I wouldn't get your hopes up too high, swapping the ECU made no difference to my starting problem, nor did it for "Bison" and I recall others in this thread.

Assuming you are still getting the fault only when the engine is hot, have you tried taking the ECU out and cooling it (waving it in fresh air for a couple of minutes)? A while back this helped in my case. The idea was that the ECU might have been overheating, although when I sent mine to be refurbished, the engineer was unable to reproduce a fault despite heating the unit.

Any other ideas, anyone? What about serious arcing inside the starter motor disrupting the signals to the ECU (someone's suggestion I recall) - has anyone tried swapping starter motors?

I also believe that the problem may be getting worse in my car; I am beginning to get a hesitation/misfire after cold starting, for perhaps 2-3 minutes, then it runs fine again. Possibly a separate problem. This week, I've cleaned my earth leads, put in new NGK spark plugs and, for what its worth, cleaned the throttle body. I'll let you know.

Cheers,
Mark

[ShadeTek]

Staurt, what happened about the immobiliser codes? Did you check this out? Why not feed a direct 12v to the coil and see if that will get your car started. My friend, the same guy who fixed your ecu before you got the car, had this problem on his jag. There was no +12v to the coil when cranked over. Seemingly for some reason there's diodes in the wiring loom which caused his problem that were going open. Introduce a clean +12v to the correct side of your coil and see how that goes.

These are the codes from your car btw.

[Chris_Rogers]

It would have been interesting to see what the 'Live data' showed at this point as it may have given some clues.
The live data shows the actual 'real time' state of the immobilizer, the codes may be historical.
These codes suggest a problem with the connection between the immobilizer (on the side of the steering column) and the antenna (round the lock barrel).
I would suggest you disconnect the battery and check the plug connection at the immobilizer and the connection at the antenna ring. Clean them and put some contact grease on the connections.
A quick check to see if the symtoms of a immobilizer failure are the same as the 'no start' condition you are experiencing is to wrap the handle of the key in some kitchen foil so the key transponder can't be read, and try to start the car.

[stuartvolvo]

Hi mark,
The reason that i am thinking of the ecu is of various reasons.
I have checked all the sensors in and around the engine and are getting good signals all the way up to the sockets at the bottom of the ecu. I have cleaned and checked the starter motor. This issue as well as being intermittant also seems to vary around the temperature. I have also checked all temperature wires and changed the temperature gauge/probe. One week she could be difficult to start when cold but easier to start when warm. Another week she could start well when cold but be difficult to start when hot. I have also bypassed the starting circuit, from the ignition switch to the starter and bypass the alarm and imobaliser, and it still has not made any difference, so the issue must lie in or around the engine.

Then on that subject, when you look at everything that i have checked, where does everything lead to, temperature, rpm, camshaft, ignition, fuel, ect. EVERYTHING goes back to the ECU at some stage, and if you think logically, everything goes back to 'and' or 'or' logic. The ecu must get this signal and that signal before it will send a spark to the coil, and when she does not start, it is because there is not signal coming from the ecu to thhe amplifier, so it looks like it could be a failing component or a cracked soldier joint in the ecu. This is at least some thing that i can look at and if it sorts the porblem, well that good. If not well at least that somthing else out of the equasion.
Ill try and look for this other ecu number in the morning when it is light and let you know.

Regards
Stuart