static timing finding position setting on ACE engine

[Francis_G]

Since I had a cambelt snap my 16V Bosch KE-Motronic injection ACE engine has been down on power and is unable to idle correctly and start with a warm engine.

 

When my mechanic rebuilt the top end of the engine and put on the cambelt he told me that he could not see a point in the intermediate shaft sprocket, as the Haynes book has a photo of it.

The car cold starts on the button, idles nicely until it gets to about 60 degrees where the engine note changes from an advance spark to one that is knocked back and at this point is stops the ability to idle. I have taken apart and serviced the TPS and that drops down to 2 ohms resistance reliably now, and I resealed it by welding the plastic casing with a hot knife. So I can now discount the TPS as a problem and the diagnostics does not flag this any longer.

 

Since the rebuild of the top end of the engine I am getting a Crank case sensor error, even tho this model does not have such a device.

 

Before the belt, travelling at 65 I could put my foot down and receive an instant surge of power from the 140 horses, since the rebuild it no longer surges the horses.

 

I know from my basic golf mk2 that when I do a cambelt change, I can do a static timing check with a gunson timing gun by having the ignition on and rotating the distributor, before fireing up, then proceed with the secondary tune up with the engine running and the vacuum hose detached from the distributor. This got me thinking "how can I do a static setup with the Bosch KE-Motronic?"

 

My thinking is as follows:

• Unplug the battery from the car
• Clamp the top camshaft sproket in place, as it is correct
• Clamp the lower crankshaft in place
• take off the cambelt
• get hold of a golf coil I have lying around that is good and hot wire it to the battery
• Connect the main ht lead to the hot-wired coil
• Plug in the Gunson strobe
• attach the hall sender of the strobe on HT1
• rotate the intermediate shaft clockwise until I get a strobe flash
• reconnect the cambelt
• The KE-Motronic should them self regulate.

I look forward to anything anyone else could add to this, as it is a technical experiment that I have thought up.

[Francis_G]

Turns out the Haynes book threw me a red herring on the ACE engine the mid shaft only runs the oil pump, therefore no need to have a timing point on the cog. I found this out after rotating it with my hot wire rig setup but nothing was happening and the wires to the coil from my golf were getting hot. I even took off the distributor cap and sure enough the arm was not moving. Even I found another string on the net that has a sketch of a hole by the bell housing that should show a timing mark, however that was not moving. Then I went back to Haynes and looked up distributor where I found, I quote “ACE and AAR engines, the distributor is located on the right hand of the engine and is driven off the rear of the camshaft.

 

After finding out my cam belt was 2 teeth out, I put all back together again, indecently the distributor cap had a mount bolt loose, that would not help. I manually cranked the engine over, no issues. Started on the button idled fine up to 60 degrees where the engine started to search again, but not as bad as before. I just instinctively unplugged the isv and she purred like a cat at just over 1k and was rock solid, plugged isv back in and the searching came back, new one on order.

 

I turned off the car, and waited 5 minutes but she would not fire up. Back to Haynes for inspiration and eventually I found a problem that I feel is the root cause,….

The connector on the loom to Part OEM 034919369C has been wired wrongly, not only that somebody tried to correct the fault by forcing the two parts upside down and the new connector is also broken. I have found a you tube person who prints new ones as the connector is no longer available. 3-pin connector 893971974. Has anyone got a wiring diagram for the correct wires to locations they could show to me so I can get this faux pas sorted out.

 

I feel close to getting this car running the way she should again, what an interesting day I have had.

 

 

[Francis_G]

I found some wiring data. I broke the connector off totally and put some heat shrink over each terminal to act as 3 individual boots. Wired upto attached diagram below, and the hot start issue has now gone, now the coolant switch is talking to the ECU.

 

I have put in the new ISV and I now have no codes being generated, for now.