mrfixit

Previously, I posted that after cleaning the battery connections my problem seemed to be fixed. Not so. This is one of those intermittent problems that is so hard to diagnose. After cleaning the battery connections, the car ran fine for two days, then died again. And, again, after sitting overnight, started right up, ran for about five miles, then quit. Still thinking it was an electrical problem, I purchased and installed a new battery. No joy, problem persisted. Following the recommendation of another poster above, I ordered a fuel pump and replaced that, only to have the problem continue. Fuel pump was not the problem (more on this below). When the car would die, I sometimes would open the hood and tap on various components to see if something would shake loose (or shake into place), and indeed sometimes this would cause the car to start. I noticed that after tapping on the upper coil, the car started. Ah-ha! I remembered that when I replaced the coil a year ago, the locking connector cracked (like so many of them do on these cars). The connector is very hard to get to, but I was able to stick a screw driver in far enough to push the connector into the connection and the car started right up. When I wiggled the connector, the car died. The wire from the wiring harness is very short for this connection, making it very difficult to keep it in place once the retaining clip breaks. I am going to have to come up with some way to make the connector stay in place better for a long-term fix. But for now, this has for sure fixed my problem. On a different note, regarding the fuel pump. I bought a cheap one on eBay, for about $50 shipped. It was visibly much cheaper construction than the original one and noticeably louder in operation when connected to the battery for testing. However, once installed there was no noticeable noise, so I left it in for now, keeping the original just in case. For a car with over 200k miles I didn't think it was a bad choice buying the cheap fuel pump on eBay, when all of the local parts houses wanted over $200 for a replacement pump. This forum has been a great help to me on many occasions, so hope this helps someone else down the road.

Just as a follow-up, I cleaned and re-attached my positive battery terminal. The post was oxidized and I don't think it was getting a good connection. I also found a crack in the accordion section of the air intake tube, which I repaired with duct tape (black of course). After driving for quite a while the engine never died. It seems like my problem may be corrected. If the problem reoccurs, I'll follow-up again.

Is there any way to test the fuel pump in this condition? Will there be any stored computer code?

My '93 LS400, with over 200k miles, just started doing the same thing. After driving about ten miles yesterday, it quit suddenly. After sitting for an hour, it started and ran fine for about five miles, then quit again. After sitting overnight, it started and ran long enough to get home, another five miles away. Once it dies, it cranks over fine, just won't start. My strong suspicion is that the problem is electrical, something gets hot then stops working. Tomorrow, I'm going to begin by checking the battery connections as suggested above. Next will be the coils, of which there are two. Seems like I had a similar problem once before and it was one of the coils.