Believe MPS is bad- now what?, Buy Rebuilt-Used |
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Believe MPS is bad- now what?, Buy Rebuilt-Used |
914_teener |
Feb 12 2011, 09:45 PM
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#1
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914 Guru Group: Members Posts: 5,208 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California |
So after about 2 years of trouble free spirited driving... looks like the MPS in my 73 1.7 D-jet gave up the ghost. Motor has some miles from the PO...don't know how many but my compression checks out fine. Right now the car won't run or start at all. My fuel pressure checks out fine.
I did all the tests on the Anders web site just to make sure the harness is okay. I did them at the ECU terminals. The car has spark. The only anomoly I could find is that the injectors tested at a little over 3 ohms... NO. 1 cylinder 4.1 ohms NO 2. 3.5 ohms. No. 3. 3.6 ohms and No 4. was 2.8 ohms. I don't know if this is acceptable and wether or not I should rebuild the injectors. Anyway then I pulled the MPS to check for vacum....no go... wouldn't even hold 1 pound. Everthing on the MPS looked stock...no screws rivets were original and still had the epoxy plug in the back. Part is Bosch NO. 0280100049. Question for the forum is: 1. Brad talks about a rebuilt units from Automotion. I went to the web site but got a gal who couldn't answer any questions about the part. I am sort of concerned about the calibration and wether or not the rebuilt part will have a problem with the mixture. Does anybody have any experience with MPS rebuilt units and maybe some other suggestions or experience with rebuilt MPS's? Should I have the mixture checked with a CO meter after installing and who rebuilds a unit that is calibrated to the stock settings? Who does the best rebuild? 2. I think I want to also have the injectors rebuilt and cleaned while I am at it to make sure everything on the FI system works for a while. Who is reasonable for cleaning the injectors? 3. Anything else I should check out while I am at it?....I am committed to FI so don't say pitch it! Thanks in Advance for Help and Advice. |
larss |
Feb 14 2011, 10:31 AM
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#2
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Member Group: Members Posts: 428 Joined: 10-September 09 From: Sweden Member No.: 10,787 Region Association: Scandinavia |
Anyway then I pulled the MPS to check for vacum....no go... wouldn't even hold 1 pound. Yes your MPS is gone so you need to replace i but the engine should still start (by the cold start at least). D-jet can be run (badly) even if the MPS is unplugged (electrically), I would check one injector and see if it is spraying. /Lars S |
914_teener |
Feb 15 2011, 12:37 AM
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#3
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914 Guru Group: Members Posts: 5,208 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California |
Anyway then I pulled the MPS to check for vacum....no go... wouldn't even hold 1 pound. Yes your MPS is gone so you need to replace i but the engine should still start (by the cold start at least). D-jet can be run (badly) even if the MPS is unplugged (electrically), I would check one injector and see if it is spraying. /Lars S Lars, Yes and it would start and then cut out.....I figure that when the idle would change or I would kick the throttle this would displace the diaphram richening the mixture and then flood...it would.... and you could see the mixture vapor from the injectors coming out the exhaust when it stalled! So I notioned either CHT or MPS. Well during the check...with the car running....I shorted to ground the CHT...as I had read was a quick test to see if it is the CHT. No problem...no effect...but when I did that once, the lead on the CHT to ground arced once to ground and then it wouldn't start at all. I am hoping I didn't short out the ECU NOW! (IMG:style_emoticons/default/headbang.gif) Anyway...you are right it should still run even without the MPS...so now I figure I need to check more things or something I did when I was testing it. For sure I need to do a check on the injectors...if not remove them and service them and have them flow tested. I am also going to check the CSV to make sure it isn't stuck open. |
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