 Injector #1 not firing, Is it the ECU |
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| DavidSweden |
 Jul 9 2015, 11:08 AM
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#1
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Member  Group: Members Posts: 479 Joined: 8-June 14 From: Sweden Member No.: 17,452 Region Association: Scandinavia  |
I am trying to figure out why my engine suddenly refused to start. This evening I was checking the injectors. I removed the injectors turned on the ignition and tested the spray pattern by opening/closing the throttle. The number #1 injector did not click /spay fuel, I took the connector for #2 and plugged it into #1 and it worked. I then removed the wiring harness from the ECU and checked for faults to ground and it seems good.
Can anyone explain why the injector does not work? I should also add that the car fires on the first start attempt runs for a couple of seconds and then refuses to start again. The plugs are dry on inspection, there is spark, timing is set and I have compression as well as fuel pressure. I have also replaced TS2 and have a rebuilt MPS. Thanks (IMG:style_emoticons/default/headbang.gif) |
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| Bob L. |
Jul 9 2015, 11:19 AM
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#2
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Senior Member Group: Members Posts: 847 Joined: 7-August 11 From: Austin TX Member No.: 13,411 Region Association: Southwest Region |
From what I have read, ECU failure is very rare. Could be a bad ground for the 1/3 injector pair or a bad connector at #1
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| larss |
Jul 9 2015, 11:56 AM
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#3
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Member Group: Members Posts: 428 Joined: 10-September 09 From: Sweden Member No.: 10,787 Region Association: Scandinavia |
The ouput in the ECU for #1 is in common with #3 so if the ECU ouput for #1 is bad also #3 would not work.
Also if only #1 was missing the engine would likely start but hunt. Im guessing on a bad ground for injectors #1 and/or 3 in 1st hand. If only #1 is missing check the connector for #1. Lars S |
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| DavidSweden |
Jul 10 2015, 11:37 AM
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#4
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Member Group: Members Posts: 479 Joined: 8-June 14 From: Sweden Member No.: 17,452 Region Association: Scandinavia |
QUOTE(larss @ Jul 9 2015, 09:56 AM)  The ouput in the ECU for #1 is in common with #3 so if the ECU ouput for #1 is bad also #3 would not work. Also if only #1 was missing the engine would likely start but hunt. Im guessing on a bad ground for injectors #1 and/or 3 in 1st hand. If only #1 is missing check the connector for #1. Lars S When I crank the engine all 4 injectors fire but when I move the throttle by hand only 3 of them fire. I guess this means that there is no problem with the injectors. |
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| larss |
Jul 11 2015, 11:01 PM
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#5
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Member Group: Members Posts: 428 Joined: 10-September 09 From: Sweden Member No.: 10,787 Region Association: Scandinavia |
When the injector does not fire is that because of the electric impulse is missing or is the injector stuck (sometimes)?
You could measure the voltage in the injector plug with a analogue instrument the needle should jump, the pulse is someting like 5V DC. Yes the ECUs wery seldom fails. Even if injector 1 and 3 always fires at the same time they m i g h t have their own output transistors in the ECU, Im not sure, if so of course one of them can go bad and measuring the output as per above should tell. If not already done also test the wire to injector no1 all the way to the ECU (wire no 3) and of course the ground wire for injector no1 (connected to ground at the multi spade connection on top of the engine case at one bolt). Lars S |
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| falcor75 |
Jul 12 2015, 04:20 AM
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#6
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Senior Member Group: Members Posts: 1,579 Joined: 22-November 12 From: Sweden Member No.: 15,176 Region Association: Scandinavia 
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David send me a PM, I have a working 2.0 ECU you can borrow to test with.
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| larss |
Jul 20 2015, 05:29 AM
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#7
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Member Group: Members Posts: 428 Joined: 10-September 09 From: Sweden Member No.: 10,787 Region Association: Scandinavia |
Any update on this..? Intrested to hear how it went...
Lars S |
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| DavidSweden |
Jul 20 2015, 05:41 AM
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#8
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Member Group: Members Posts: 479 Joined: 8-June 14 From: Sweden Member No.: 17,452 Region Association: Scandinavia |
QUOTE(larss @ Jul 20 2015, 03:29 AM) Any update on this..? Intrested to hear how it went... Lars S Lars, I wasted a lot of time by jumping to conclusions. eventually I followed members advice. See this thread |
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| larss |
Jul 20 2015, 05:59 AM
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#9
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Member Group: Members Posts: 428 Joined: 10-September 09 From: Sweden Member No.: 10,787 Region Association: Scandinavia |
QUOTE(DavidSweden @ Jul 20 2015, 01:41 PM) QUOTE(larss @ Jul 20 2015, 03:29 AM) Any update on this..? Intrested to hear how it went... Lars S Lars, I wasted a lot of time by jumping to conclusions. eventually I followed members advice. See this thread Oh that was sad to see..possibly and hopefully damage is to the heads only but thats bad enough :-( Lars S |
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