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. |
BeatNavy |
Jun 28 2015, 03:34 PM
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#2
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Certified Professional Scapegoat Group: Members Posts: 2,924 Joined: 26-February 14 From: Easton, MD Member No.: 17,042 Region Association: MidAtlantic Region |
Hey Bob - sorry to hear you're still chasing this. It is a good feeling knowing your injectors have been serviced and not the issue, though, and Mr. Injector does do a great job.
I was having similar issues, and I wish I could say I found a "smoking gun." I did replace the wiring harness with a "Bowlsby-special," and my problems are in fact gone. It's hard to tell if that was 100% the cause, because I initially struggled to get the grounds wires connected securely, and I also had an issue with a loose fuel pump connection at the relay board on the new harness (cut out on me near my house). I also replaced the spark plug wires and tried to make sure they routed clear of other wires (especially #3 which apparently sometimes causes electrical interference). Everything is running like a champ now, though, particularly after doing some MPS fine-tuning. If you can, I'd definitely consider investing in the new FI harness, as it can help eliminate a lot of potential variables as you disconnect/reconnect sensors and other odds and ends. Do you have an O2 sensor? Did you inspect/replace the TPS or just calibrate it? Is the MPS actually steadily holding a vacuum? That's all I got...sorry. |
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