No Start - Broken MPS Wire |
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No Start - Broken MPS Wire |
MDTerp |
May 8 2022, 07:36 PM
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#1
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Member Group: Members Posts: 103 Joined: 20-May 08 From: Maryland Member No.: 9,075 Region Association: MidAtlantic Region |
I spent the weekend trying to diagnose a no start issue with no luck. Here’s a short description of the condition and what I’ve already checked. Any help is appreciated.
Drove the car to Carlisle two weeks ago, 180+ miles round trip with no issues. Tried to start a week later and the engine cranks but won’t catch and doesn’t sound like it tries to catch. 1975 2.0 D-Jet with 74 Case/Heads/Exhaust and 75 ECU/MPS 4k miles on engine rebuild and car has always started up easily and idled well Stock Cam 8.0 EU Pistons 123 Ignition Distributor - Installed last year Bosch Blue Coil - Installed last year FJ67 Fuel Injectors - Installed with rebuild I always try to look at the last parts I touched which were: Replaced hose between expansion fuel tank and filler neck Added heater hoses between electric fan and J pipes (both done after trip and before no start) These don’t seem related but I assumed I bumped a connection loose somewhere when installing the hose to the J pipes but I couldn’t find anything. Checked fuel pressure at front side of the rail of cylinders 1&2 which was 28 psi when key in on position and while cranking. It slowly drops over 20mins or so. Pulled injectors from 1&2 and cranked with injectors in bottles. I confirmed fuel spray, although it didn't seem consistent. Connected a timing light to coil, battery and #1 spark plug wire and the light would not flash when cranked. Pulled cylinder 4 spark plug wire and saw weak yellow spark with spare plug attached to wire and threads held against ground. Checked #7 pin on 12 pin connection on relay board and measured 12V to ground with key in on position. Checked positive side of coil to ground with key in on position and measured 12V to ground. Pulled distributor cap and everything looks new and normal. Replaced Bosch Blue coil with older coil (which worked when removed) and no change in starting. This also gave me an excuse to replace my 10+ year old battery so I have a new charged battery and no change to the no start situation. This week I will pull the plugs and see if they are fouled. I might try replacing the 123 distributor with the old stock one. I also have a spare 052 ECU I can try. I'm sure this is something stupid I missed. Edited: fixed typo for clarity |
Mikey914 |
May 11 2022, 10:36 AM
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#2
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The rubber man Group: Members Posts: 12,711 Joined: 27-December 04 From: Hillsboro, OR Member No.: 3,348 Region Association: None |
Try to fix 1st if not there are options.
.......just more expensive. |
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