DTAForum.com - a forum for the DTA ECU

Hi,
Although I'm new to this forum I've been running a DTA ECU on a 20xe since 2000. Until recently it has been almost faultless. My ECU:
purchased in 2000
Model 4/IGN (not sure if this is E48 or an earlier model)
Version V6.0
Firmware V22.0
Serial No. 2248
Engine Vauxhall 20xe with DCOE45 carbs.
The problems started about a week ago when the engine cut out with banging in the exhaust. The only problem I've had in the past was due to the throttle position sensor so I disconnected it and managed to get it started and got home. I replaced the throttle pot, set the stops and tried to start it. Starting was extremely difficult with popping and vapour coming out of the carb intakes as if the timing was out. When it did start I checked the carb balance and then shut it down. It would not restart.
DTAwin Diagnostic Display showed Crank Sensor Errors = 0: Water Temp=85 short term errors: , Air Temp = 86 short term errors and Pressure sensor = 85 short term errors. This is a little strange as these sensors don't exist and should default to 80 C, 50 C and 0 kpa respectively.
I've checked the log and during startup the numbers are all over the place:
Time 0.0.6, RPM 446, ADV 90, INJ 0, THROT 19, W/Temp 188, PRESSURE 32609, CRANK ERROR 1, LAMBDA -7149, REST COUNT -16382.

If advance was really 90 then it explains why it would not start but what is causing the other numbers.

When it was running the log shows:
TIME 0.16.7, RPM 637, ADV 16.4, INJ 1.00, THROT 19, W/TEMP 80, PRESSURE 0, CRANK ERROR 9, LAMBDA 0, RESET COUNT -16425.

I checked the crank sensor as best as I can. It has a resistance of 534 ohms across pins 1 & 2.
So could a dodgy crank sensor cause this or is my 17 year old ecu failing.

Any help/advice greatly appreciated.

Pete

Try reloading your map if you kept a copy of the original one( you should have)

I have seen this happen before and that fixed it. I know it seems strange but you will have to try anything as the E48i will usually be ok.

Tony.

Thanks Tony. Will reload and see what happens.

Have reloaded map but unfortunately still the same problem. I'm about to bypass the power relay to rule it out of the problem.

Checked the power relay and FIA cut-out. Both seemed OK so reassembled and low and behold it started instantly. The log shows Crank Error 3 and 4. I'm sure when I've looked in the past it was always 0 so it looks as if the crank sensor is on its way out. I'm still not certain of the cause so I I will replace the crank sensor, power relay, cut-out and re-check all the connections.

After you reloaded the map did you switch it off then on again? you need to do this on an E48/E48i to make it recognise the new map is loaded. otherwise it will be the same as before.

Thanks Antral. Yes I did turn off on on again . Been running ok for about 50 miles then today I started to get brief engine cut-outs so looks like I have to get into diagnosis mode again. One thing I did notice about the ecu is that it runs very hot. It must be 70-80 C. I have never noticed it to be this hot before. Is this normal for this ecu?

Yes they do run quite warm, check your Coil on time is not too high but I suspect the ecu is ok.
The crank sensor or wiring should be inspected if you get a few crank errors.

Coil on time is 3600 microseconds. Checked the log and found crank errors were 12 or 13 from the last run. Started from cold this morning; Engine Diagnostic Display showed Crank Wheel Teeth Errors at 3 to 4 but gradually increased to 7 - 8 after few minutes. So appears I have either
1. Faulty crank sensor - it is a new Bosch one and when first installed showed 0 - 1 crank wheel teeth errors. Have checked it is mounted correctly in case the gap to the teeth was increasing as the engine heated up.
2. ECU has a temperature related fault
3. Wiring or connector temperature related fault.

Have I missed anything?

I think reduce your coil on to 3000 unless you know you need it set higher.
Check all engine grounds. check ecu ground and make sure that the screen wire for the crank sensor is all good.