Hello all ...

My wife and I went out this morning to run our normal Sunday errands. We pulled up to the first store, shopped, returned to the SC400 and she started right up. We then drove to our next stop where I was in-and-out in 5 minutes. I got into the car and turned the key ... but it wouldn't start! The car turns over like a champ but it just wouldn't "catch". We called a tow truck and waited. 30 minutes later I mentioned (as a joke) that I was tired of waiting and that I was now going to drive home. I turned the key and BAM ... she starts right up! I drove the 5 miles to the house and parked her in the garage.

I found it interesting that once she was parked I turned her off ... waited 30 seconds and then tried to start her up again but she did not want to. She turns over and all but wouldn't start. I was hoping someone else had had similar/same issues with their car in the past. I suspect the fuel sender/pump but am not ruling out the fuel filter.


Car details:
1993 SC400
EXACTLY 57,000 miles
Tank is 95% full of premium 93 octane



Please provide guidance if you can ... thanks!

 

Sounds like a ignition issue for some reason? cause usually theres enough fuel in the system to at least run for about 10-15 seoncds before it would die.

 

fuel pump ECU - bypass it.

mine did the exact same thing, then it wouldnt start at all. I tried all kinds of stuff - fuel filter, AFM, even changed the fuel pump. Once i bypassed that POS fuel pump ECU, runs like a champ again.

 

Please explain how I would bypass the ECU ... and did you do it permanently? How do you know if an ECU goes bad? I have replaced my engine ECU only because it was the last part I hadn't tried and that was it.

I appreciate your frankness ... I wish to avoid what you went through replacing everything but the right part. How great would it be if I replaced the faulty part the first time around?

Thanks ...

 

I had somewhat of the same issue. Mine turned out not to be the fuel pump at all. I actually had a loose connection in my engine compartments fuse box. You can also try pushing or swapping out the EFI relay (closest round relay to engine) or the 30 amp EFI fuse might be blown or loose. Hope this helps.

 

My issue is very weird and VERY intermittent. Yesterday I went out and tried to start the car twice and it started beautifully. After stopping the engine it would not start on attempt #3 but for some weird reason it started over and over again from attempt #4 to #10.

I tried reading the OBD I codes but nothing came of it (no codes). Because I had a hard time replicating the problem I was not able to short the fuel ECU via the diagnostic port in the engine compartment.

Any more ideas?