This has had me really scratching my head for the past two weeks and I'm getting to point where I'm going to start swapping out relays and whatnot, but I'd rather troubleshoot things a better way. A little background, this is a turbo wagon with 170k miles with a pre-pump and main pump, and is a bit rusty. Two weeks ago the fuel feed line rotted out and started dribbling gasoline on the ground, so I took it all apart, ordered a new line and fuel filter and cleaned up the housing and put everything back together. Immediately the car ran terribly, it died out when I put anything but the lightest throttle and misfired like crazy. I jacked it back up and noticed the wire to the fuel pump's positive connector had been previously soldered and was falling apart. I clipped it off and noticed the plug was corroded and falling apart as well. So I pulled off the female ends from the pump and crimped some butt connectors on to connect everything up. It ran like normal for a day, and then the wiring fell apart so I re-did it (a few times), eventually getting everything on pretty snug. Now, however, the car still began to run terribly and die after 20-30 minutes of driving and I still was stuck on thinking it was a bad connection somewhere due to road vibrations. That is until I noticed that no matter how I tugged at the wires it neither caused the car to sputter or die, and when it is running very rough tugging at the wires does not effect it. Basically there is something else wrong now.
I can deduce that the car can idle 15 minutes or so from cold, with poor but not terrible idling and thottle response, before it starts to misfire, and all the while it smells like it's running very rich (I will have to check the oil). The tachometer drops to zero and goes back up when it is sputtering out, and the smell of gas is still prevalent, as well as very rough idling, and eventually the car dies. I've noticed that if I turn the key to KPII the pump does not start the first time, but if I bring it back to KPII I can here it turn on the second time and it *often* starts for awhile and runs poorly for a few minutes before dying again. I can't just turn the car over after it dies, it won't fire. If I let the car cool off for a half an hour then I get better performance but only for fifteen minutes or so.
I hooked up a voltmeter to the leads to the fuel pump and I get ~12.9V during idle, and drops in voltage to ~12.3V-12.7V when i rev the engine up. It averaged up ~13.1V after I removed the fuel pump relay cover, added some dielectric grease and re-seated it, but that probably doesn't mean anything. When the engine is just turning over and not starting (after it dies on me) I get a reading of ~11.8V, but that goes away if I bring it to KPII a couple times. Weird.
After reading a few FAQs, I still have to try replacing the ignition control module, fuel pump relay (I opened it up and it looked alright, but it was getting hot to the touch as the car idled which isn't a good sign?), the radio suppression relay, fuel pressure regulator (I'm sure this isn't the cause), the ECU, and cleaning the air mass meter and idle air control valve.
My biggest question is what do you all think could have happened? Could the bad connections during my initial repair have caused some electronics to fail? And why does it get worse when the car runs for awhile, and then settle down after a half hour (guessing overheating somewhere)? The rich smelling gas fumes also gives me the idea that maybe the engine is slowly flooding so eventually it dies out when I hit the gas?
The closest thread I could find with similar issues was on another forum, but there wasn't any solutions given :/ http://www.volvo-forums.com/t36228-1994 ... alling.htm
I would really appreciate any questions and advice, and sorry if I wrote too much I've just been stuck on this problem all day. Thanks everyone!
edit: Another clue and coincidence, the third time the car died on me (third tow) the alternator belt snapped and then after my fourth tow last weekend, the (second) fuel feed line came and I bought a new belt today and installed them. The first thing I noticed was this strange static on the radio, loud and persistent. I thought it was strange but figured I would just have to clean the radio's rheostat later, but then the car died on the road a FIFTH time today (my mother was driving) and I had to have it towed home again (thankfully we have AAA premium), and so I finally started looking online for answers because I knew it just couldn't be a bad connection at the pump anymore. So does anyone have a clue what the Radio Suppression Relay does? I didn't think it would literally have to do with the radio but maybe it does. I am definitely going to the junk yard tomorrow and picking up a bunch of replacement parts. I was talking it over with my dad and maybe the high resistance of the poor connections caused a high draw of current that might have burnt out some electronics, hopefully not the ECU.
94 940 Turbo Sputters, Misfires and Dies after 10 minutes
Thanks for the tip. I replaced it last year after it started running terribly after cleaning the intake manifold and washing the block, I guess the grease and water really messed it up. I could always replace it again, but I am going to try the radio suppression relay and ignition control module first (Ideally I'd replace the whole piece of wiring harness from the fuel pump to the fuel pump relay but I really don't want to take apart the interior.)
-
- Similar Topics
- Replies
- Views
- Last post