Fuel Injection diagnostic 103 engine. Need advice.
I am usually pretty good with repairs. I just re-did my own head gasket on this car. I have always had some troubles with this car's injection, but lately, it's become intolerable.
The residual fuel pressure appears to drop to near zero fairly quickly after shut off. I say this because cold or hot, the engine takes from two to 30 seconds to start. The time seems random.
I do not have a fuel pressure guage, but I come to the pressure drop conclusion by doing this layman's test. Run car. Shut off. Loosen a fuel distributor fitting. --squirt-- Run car again. Shut off and wait five minutes. Loosen a fuel distributor fitting. -a drip-
Some months ago, I replaced one of the two fuel pump check valves (it has two fuel pumps connected in series). No cure. I then replaced the other one, which in hindsight was a little silly.
I tested the cold start valve by removing it with the steel line attached and re-attaching it to the valve body, but pointed up in the air. I plugged the hole in the rubber boot below the CSV and ran the car. No leak. No seepage.
Tested the accummulator for a blow-out by pinching shut the fuel return line. Ran the engine. Shut it off for ten minutes. Started after ten-30 seconds cranking.
OVP is fine, because all systems operate fine and I get no engine light. The car once started idles and runs fine.
I tested the resistance on the (name forgotten) on the side of the fuel distributor, and it is exactly on spec at 19.5.
Tested the fuel pressure regulator by a tech CD recommended procedure of removing the fuel return line side and looking for more than a drip. I didn't get more than a drip...
I can't imagine that this has anything to do with the O2 sensor, but I'm ready to try anything.
I need to further narrow this b@$tard problem down, and need some professional advice before I hand over my wallet to the dealer.
Many, many thanks in advance.