81 spyder 2000 FI

[81spidr]

My car has recently gotten to the point where it starts cold fine but after it warms up it it doesn't want to start back up. it almost acts like a vaper lock. it will turn over and over several times before getting started but every time gets a little bit worse any thoughts????

[So Cal Mark]

check to see if it holds fuel pressure when you shut it off

[81spidr]

I checked the fuel pressure and have 38 with the key on and 28 when running. I think it may be linked to another gremlin i'm fighting. the dual relay doesnt always make a connection by itself and i reach under the dash and make the 2 relays connect by pushing them together (we took the cover off the relay). Once started it runs like a top and really pretty dependable. thanks for your reply Mark.

[So Cal Mark]

28 running sounds low

[zachmac]

I checked the fuel pressure and have 38 with the key on and 28 when running. I think it may be linked to another gremlin i'm fighting. the dual relay doesnt always make a connection by itself and i reach under the dash and make the 2 relays connect by pushing them together (we took the cover off the relay). Once started it runs like a top and really pretty dependable. thanks for your reply Mark.

I STILL say you have weak voltage to the dual relay coils! You need to recheck all the connections that feed power to the relay coil for the fuel pump. You shouldn't have to close those contacts by hand! (Have you tried just replacing the relay, they don't cost a fortune?) BUT, I agree with Mark. You running fuel pressure should be higher. Is the vacuum line to the FPR intact AND does it provide a vacuum? My line was fine but the port at the intake plenum was all plugged up.

[81spidr]

I did buy a relay and it does the same thing atleast using the old one that has the cover off i can drive it. I sent the new relay back to IAP, they put in 3 or 4 cars there and it worked fine so they sent it back n/c. as far as the fuel pressure being low we got some specks and they seemed to be in range. Hope to get lookin at is in the next few weeks but been busy running freight.

[htchevyii]

28 running sounds low

Brad Artigues FI manual says 28psi with the regulator connected and 33-39 without, I was just looking at it today.

[So Cal Mark]

see, that's what I get for replying without a manual in front of me It still sounds low to me though

[81spidr]

After running several test we are at the point where according to the Bosch trouble shooting manual says the ECU is bad based on testing for ground at terminal 17 on ECU connection. ( book says if test light comes on when checking between terminals 1 and 17, the ECU is bad).Is there any way to further test the ECU? The car runs fine if you manually make the combo relay coils close (with cover removed from relay).

[rlux4]

If there is another component that is faulty the troubleshooting guide can give you a false result as far as the bad ECU goes. I ran into this when I first got my car and was having intermittent problems. The only sure way to test if you have a bad ECU is to replace it with a known good one. I'm betting that your ECU is OK. I think Zachmac is onto the right culprit. There are four power lines at the dual relay: Pink w/ black wire from fuse #1, red w/ black wire from the ignition switch, brown w/ white wire from the inline fuse behind the fuse panel, and the large brown wire (unfused) direct from the battery. Make sure you have consitent and full voltage at all four sources.
Ron