2G Car wouldn't start until I activated Fuel Pump Via DSMLink

[DSMsOwnYourV8]

So my car has been running great, but today I couldn't get it to start. It wanted to crank over, but just wouldn't. My battery was fine because I had power in everything, so I went into DSMLink and activated my fuel pump. Problem solved

My question is what does this mean, wiring issues? It didn't seem to be an issue before? I've put almost 800 miles on this setup with no issues, but today it was a problem starting?

Mods list is in my profile.

 

[ExpresS]

Interesting....

 

[DSMsOwnYourV8]

Anybody?

 

[bo0st]

Wow that's weird. I might get the AFX ECU instead of MS now if I have to "tell my car to start" .

Hope someone can chime in here with more information!

 

[99_eclipse_gs-]

Is it possible you turned off the fuel pump on your last tune, I'm not too familial with tuners and programmers but if you can turn it on, you can turn it off. Have you had any issue with it sense or is this a one time thing?

 

[luv2rallye]

The ECU turns the FP on based on receiving CAS pulses. Perhaps you have an intermittent CAS, or intermittent ECU, or intermittent MFI relay since it provides power to the CAS. Or intermittent wiring of any of these.

 

[91awd26]

+1 on the MFI Relay. Had this problem with my old GSX and it was the wiring going to/from the MFI Relay.

 

[DSMsOwnYourV8]

Ok thanks guys for the thoughts. I'll check into it

 

[miguelmcv]

Couldn't it be a malfunction CAS?.

I know the CAS send pulse signal to the ECU and the ECU triggers the Fuel Pump.

So, If the ECU is not getting the signal, then It will not turn ON the Pump. That's why, You can turn it ON with LINK.

Don't quote me on this, But I think this is the way it works.

Hopefully, some one with more knowledge on MFI System will chime in...

Ho, I don't think that you have a wiring problem from the ECU to the relay, pump, or a bad Fuel Pump, Because the pump is able to turn ON and OFF with LINK, so there is no malfunction or wiring issue from the ECU to the PUMP.

There could be a malfunction or wiring issue from the CAS to the ECU, or the ECU by it self, But I don't think is the ECU which (LINK can still turn the PUMP ON).

 

[DSMsOwnYourV8]

Ok well the car did the same thing again today and this time The pump would not turn on via DSMLink. I ordered the relay today for the fuel pump because it was only $10.

I'll look into the CAS as well. The only other thing I could think of is a faulty fuel pump.. If I can find a friend with a Walbro lying around, I might throw that in there and see if it makes any difference.

 

[Blitzdvr4]

ever find the solution to this?

 

[DSMsOwnYourV8]

ever find the solution to this?

I replaced the Deatschwerks 320lph that I had in there with a 255 and the problem was solved. The fuel pump was under warranty, so I sent it back to Deatschwerks and they tested it and said it was fine. However, they said they would send me a new one, anyway.

I hadn't encountered this issue again until this morning when I went to crank over the car and it acted like it wasn't getting any fuel pressure again. I can hear that the fuel pump isn't turning on, but I didn't have time to get my laptop and turn it on manually again via DSMLink.

I have a 6 bolt in it so I'm going to look into changing the cam angle sensor and hope this solves it. It's just really weird that it is an on and off issue like this, and every indication was that it was the fuel pump 2 years ago, even though Deatschwerks said it wasn't, and now the problem is re-occuring again.

 

[LouieAWDTSi]

After getting professionally tuned a few hundred miles ago (v3full), my car will not start today. Happened out of no where. Going to use this thread to try and take the right steps in solving this issue. suckkkksss

 

[SAUBIK]

After almost 13 years I'm re-opening this thread and I want to tell something about it. I had similar problem after complete rebuild from NA to Turbo. Custom wiring, but majority of cables stayed stock. Just rewired fuel pump.

I used 95 ECU what have reversed sensors by 90° - I made everything, but car while cranking still not turn on fuel pump. I tried NA ECU and it start fuel pump for 4 seconds after I turn the key to ACC position, so relay, wiring and fuel pump working properly.

If I put 99 blackbox ECU in it, still fuel pump doesn't work, so I put back the 95 ECU and hardwired ACC signal to back relay to forced start of fuel pump and while ACC it still pump and after this car start like charm. But if I stay with key in ACC, it is little disturbing hear whining of fuel pump.

So I want to know, what wire I need to check while cranking to start fuel pump if I want to check signal out of ECU.