Homer Posted September 19, 2008 Share Posted September 19, 2008 Have you checked the relay? Does a std fuel system run a relay? The TT has two relays for the fuel pump, not sure what the issue is if all the fuses are okay. However it does indicate a signal cut in the engine bay area if the pump runs when the diag ports are bridged. Quote Link to comment Share on other sites More sharing options...
supratoy Posted September 19, 2008 Author Share Posted September 19, 2008 Have you checked the relay? Does a std fuel system run a relay? Yeh they are ok, i even switched them around jsut incase but just did the same. Could CW be right and its just the alarm? If its the alarm would bridging the diag port still make the car start? Quote Link to comment Share on other sites More sharing options...
Ryan.G Posted September 19, 2008 Share Posted September 19, 2008 (edited) In order for the fuel pump to become active, first the Main relay system must be active (ie B+).... As you have bridged FP and B+ and its works then the Main relay system is active. So for the fuel pump to become active from here, the Stock ecu sends a 5v-12v signal down the FPC pin to the Fuel pump computer when the IGN is first turned on to prime the pump and then when an RPM signal is seen on the ecu. This will then flick over a breaker so to speak which sends the B+ (12v) signal down the FP + So as Gav said. Check when turning on the Ign that the pin FPC is showing 5-12v. It will only do it for 3 seconds so make sure you have the multimeter connected before turning on the IGN. If you have 5-12v on this wire then you have an issue with the FPC or other wiring to it. IIRC it has 5 wires going into it. DI, FPC, B+, FP, GND DI = Sends a feedback v back to the stock ecu to let it know what v it is running FC = Voltage control signal B+ = 12v FPC = Output for fuel pump GND = Ground HTH Ryan Edited September 20, 2008 by Ryan.G (see edit history) Quote Link to comment Share on other sites More sharing options...
supratoy Posted September 20, 2008 Author Share Posted September 20, 2008 In order for the fuel pump to become active, first the Main relay system must be active (ie B+).... As you have bridged FP and B+ and its works then the Main relay system is active. So for the fuel pump to become active from here, the Stock ecu sends a 5v-12v signal down the FC pin to the Fuel pump computer when the IGN is first turned on to prime the pump and then when an RPM signal is seen on the ecu. This will then flick over a breaker so to speak which sends the B+ (12v) signal down the FP + So as Gav said. Check when turning on the Ign that the pin FC is showing 5-12v. It will only do it for 3 seconds so make sure you have the multimeter connected before turning on the IGN. If you have 5-12v on this wire then you have an issue with the FPC or other wiring to it. IIRC it has 5 wires going into it. DI, FC, B+, FP, GND DI = Sends a feedback v back to the stock ecu to let it know what v it is running FC = Voltage control signal B+ = 12v FP = Output for fuel pump GND = Ground HTH Ryan Which is the fc pin? we are meaning one of the connectors on the fc ecu yeh?[OOPS][/OOPS] Quote Link to comment Share on other sites More sharing options...
Ryan.G Posted September 20, 2008 Share Posted September 20, 2008 First of all made a small mistake in the pin name its actually FPC, This pin can be found on both the ECU and the Fuel Pump Ecu Easiest place to check if it has Voltage is at the ecu in the passenger foot well. Its on connector E10 and pin 22 Ryan See below for pinouts, http://www.mkivsupra.net/vbb/showthread.php?t=35919&highlight=pinouts Quote Link to comment Share on other sites More sharing options...
supratoy Posted September 21, 2008 Author Share Posted September 21, 2008 First of all made a small mistake in the pin name its actually FPC, This pin can be found on both the ECU and the Fuel Pump Ecu Easiest place to check if it has Voltage is at the ecu in the passenger foot well. Its on connector E10 and pin 22 Ryan See below for pinouts, http://www.mkivsupra.net/vbb/showthread.php?t=35919&highlight=pinouts Just had another go at the car, I think I need to give up though. The car fired up for some strange reason(this is without bridging the 2pins in the diag port together) , but it was reading very lean on the afr gauge. After trying to get a reading from the pfc pin (It read 2-3volts but it stayed at 2-3volts) while ignition was on. I tired to fire the car up it it started(now the car is reading very rich and when you rev it a little alot of fuel came out the exhaust. Turned it off then fired it back on then again but eventually died and wouldn't start. I thought Ill check if the reading from the pfc pin was correct the first time round so thought I better double check, it read 2-3volts, when I tired to fire the car up it would fire up but running very rich on the afr gauge and now the engine management light is on:blink: So annoyed not even sure if any off the above makes sense. Quote Link to comment Share on other sites More sharing options...
supratoy Posted September 22, 2008 Author Share Posted September 22, 2008 ok very last try, I got fault code 31 and 78. 31 fault being- open or short in air flow meter circuit, air flow meter, ecu 78 fault being- open or fault in the fuel pump ecu circuit,fuel pump ecu, fuel pump, ecu power source circuit and ecu. I dont think its the fuel pump or the ecu but how do I check for the others? What should I do now? Just take it to a garage:blink: Quote Link to comment Share on other sites More sharing options...
JustGav Posted September 22, 2008 Share Posted September 22, 2008 Going to default to CW's thinking... Unless you are very unlucky to have both the AFM and FPC go bang, you have a wiring loom issue. Check that the connectors are tucked neatly into the ECU, they do have a habit of coming out (read getting caught, ripped by people not being too careful) Jspec/UK? VVTi/Non? There is a reason for asking Quote Link to comment Share on other sites More sharing options...
supratoy Posted September 22, 2008 Author Share Posted September 22, 2008 Going to default to CW's thinking... Unless you are very unlucky to have both the AFM and FPC go bang, you have a wiring loom issue. Check that the connectors are tucked neatly into the ECU, they do have a habit of coming out (read getting caught, ripped by people not being too careful) Jspec/UK? VVTi/Non? There is a reason for asking Its a Jspec. All the wires look to be all ok and cant see any to be loose or damaged. Quote Link to comment Share on other sites More sharing options...
tDR Posted September 22, 2008 Share Posted September 22, 2008 Do you have a boost gauge or controller plumbed into the same vacumn line leading to the MAP sensor on the intake plenum? Quote Link to comment Share on other sites More sharing options...
supratoy Posted September 23, 2008 Author Share Posted September 23, 2008 Do you have a boost gauge or controller plumbed into the same vacumn line leading to the MAP sensor on the intake plenum? I have a gauge but dont think its plumbed into the map sensor:( Iam just going to get someone to look at it, its taking to much time to figure it out:( cheers for all the help everyone:) Quote Link to comment Share on other sites More sharing options...
mikeyb10supra Posted November 30, 2009 Share Posted November 30, 2009 Was this ever sorted mate? Sorry for bumping an old thread, only im having similar issues now Quote Link to comment Share on other sites More sharing options...
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