Fuel Injector Going Bad?, FIXED - Thanks 914 World! |
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Fuel Injector Going Bad?, FIXED - Thanks 914 World! |
saigon71 |
Jun 10 2015, 07:32 PM
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#1
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Advanced Member Group: Members Posts: 2,000 Joined: 1-June 09 From: Dillsburg, PA Member No.: 10,428 Region Association: MidAtlantic Region |
74 2.0 D-Jet. Car is in a fine state of tune. Verified fuel pressure at 30 PSI. Removed distributor, cleaned & lubed advance plates and tested vacuum canister. Verified TPS is set correctly. MPS tested fine. ORIGINAL fuel injection harness. I went around the engine bay today and re-seated all FI related connections. The injectors are in unknown condition - came with the car.
This is different than the bucking I used to experience. I intermittently have a cylinder drop off. It happens at all speeds, but is really noticeable at idle. I had it running for a while in my driveway tonight and the exhaust fumes spelled especially "gassy." When it's not missing, it runs fantastic and idles perfectly. I think I have a fuel injector going bad. Can they fail intermittently? Anyone else experience something like this? I figured I would just pull all four injectors, run the fuel pump and measure the fuel...but I'm not sure I could find the faulty one if it functions correctly during the test. Pretty boring video (IMG:style_emoticons/default/dry.gif) Engine starts running rough intermittently at :40 (engine bay sound) and 2:07 exhaust. https://www.youtube.com/watch?v=xQoMS-NeOag...eature=youtu.be Any advice is appreciated. |
DRPHIL914 |
Jun 11 2015, 06:45 AM
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#2
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Dr. Phil Group: Members Posts: 5,768 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States |
i had a similar issue with my75 d-jet and thought it was an injector, sent them in for testing and cleaning and they were spot on and flow was within1% of each other, not bad for 40 year old car - but here are 4 things to check ive had each of these at some point in the 6 years of owning the car
1. the F.I. grounds , they can come loose and will feel like you are firing on 2 not 4. 2. F.I. trigger points plate - usually dont fail but you can pull them and clean them 3. Recently this happened for no apparent reason- Bad cap/rotor - acted just like a bad injector or plug or wire, it was intermittant and would happen if i did not drive the car for a few days which made the mechanic think it might be a bad injector sticking open, if i got the car started(sometimes it would not ) it would clear out and be fine for a few days - but also seemed to be effected by temperature or humidity- it was so simple but one of the hardest things to chase - ended up being the spring in the center connector of the distributor that goes to the coil, so it would not always make good contact. 4. old wiring harness shorts etc- I replaced mine with a new one from Jeff Bowlsby . Now i know i have good connections and no shorts due to cracks in the old insulation. Good luck!!! |
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