Hi all,
Bought a 1991 240 wagon for my daughter. 2.3 L engine, FI (not sure which type), automatic. In the last three weeks it has failed to start, on the first occasion, the shop found that the fuel pump fuse had blown and blew for them once replaced. They had done a tune-up a few weeks prior, and found that the plugs were fouled. They traced the fuse problem to the wire from the fuel pump relay to the pump; which they replaced, new plugs as well (free). About ten days later, no start again. I did some of the basics (jumped fuses 4 and 6, heard the pumps running, pulled a plug to confirm strong spark) but still no joy. Back to shop, they diagnosed flooding; with gas in oil and plugs wet with gas. Changed oil (needed it anyway), new plugs again (different type) and seems to be running well. What are some of the likely causes of the flooding? What can I test/replace on my own to prevent future occurances. I want the car to be reliable for my daughter, while hoping to avoid $$$ tows and troubleshooting.
Thanks,
Bob

One other possibility is that someone has tried to "fix" a bad ECU here. I've seen a few of these 89-up cars with jumper wires added to force the fuel pump on. Basically it's to add a ground path to the fuel pump- when the ECU goes bad, it no longer supplies a ground to the pump. The net result is, the main pump runs ALL THE TIME when the key is on. This doesn't sound like much but it's enough to flood a car, and sure, it could do weird things like blow a fuse.
Normally the pump doesn't start until the engine is turning and the ECU is receiving pulses from the crank sensor.
You'll be able to tell if someone has "hacked" the wiring here- simply turn the key to ON and listen under the car- if the fuel pump's buzzing constantly, while the engine is NOT running, you should pursue this problem.
The fix is probably: replace the ECU, then cut the jumper wire that was added to the harness (probably right next to the connector for the ECU, in the right kick panel.) It's probably obvious what wire was tapped into- it won't look like neat factory wiring.
I'm not ruling out the other suggestions about the FPR- this is just an alternative path that's not-so-obvious.
Hope this helps!!
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Rob Bareiss, New London CT ::: '87 244DL/M47- 225K, 88 744GLE- 209K, 91 244 183K. Also responsible for the care and feeding of: 88 745GLE, 229K, 88 244GL, 146K, 87 244DL, 235K, 88 245DL, 236K

Sometimes a failed/failing fuel pressure regulator will allow the rail pressure to exceed specs which can lead to too much fuel.

Randy

Also check the vacuum line to the FPR. If this is split or loose, the FPR sets maximum fuel pressure and the car runs very rich.

Yes and symptoms of a bad FPR is rich running and gas in the oil. Get a new one and replace it yourself, easy fix. Good luck Dan
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85 245 M46 188K, 92 245 A70 115K