ok as some would know im having a miss with my engine and im pretty sure now its from running really rich, today i installed my new(secondhand) iac valve cleaned up idle a lot, gave the accelerator a stab cough splatter etc etc noticed clouds of black smoke so symptoms so far: -missing when hitting the accelerator -plumes of black smoke -takes a while to start when cold sometimes two attempts -lacking a little power upto 1700 rpm -when fuel pumps running without engine going the regulator at the fuel rail, it will make it normal noise than at random intervals it will make a very loud shhhhhhhhhing noise that dosnt sound too normal start throwing up some ideas for me guys will be much appreciated Andrew
yep no codes, yeah i thinks both my oxy could be on there way out but i wanna make sure before i fork out 260 for two sensors
Get a magnifying glass (no bull) and check your coil pack (look for a hair line crack).Thats what happen to bro's car,took me 2 days to found out.
Probably way off track but could it be the oil pressure sensor supplying intermittent power to the fuel pump resulting in erratic fuel supply (you say: "when fuel pumps running without engine going the regulator at the fuel rail, it will make it normal noise than at random intervals it will make a very loud shhhhhhhhhing noise that dosnt sound too normal" ....with the engine stopped but ignition on the fuel pump should not be pumping. Also could it be the fuel return hose inside the fuel pump dislodged (causes erratic fuel supply when less than 1/2 a tank left). Coolant temp sensor telling the ECU the engine is still cold. Blocked air filter. Good Luck.
I think hako might have latched onto a clue there. When the fuel pump relay (or something in that circuit) fails, the oil pressure switch is able to take over its duty and supply power to the fuel pump. I have never experienced this, but I hear this causes the car to take a long time to start. I do not know whether the oil pressure stays high for a while after the car is stopped or if it drops immediately, but if it does stay high, this could explain the pump running continually with the engine off (does it do it if you havent tried to start the car for some time? or is it only after trying to start it?) Try listening around the engine bay to see where the noise is coming from. My spidey sense is tingling and its making me very suspicious of the fuel pressure regulator.
I'm pretty sure I mentioned the regulator in your other post. It shouldn't make any noise at all, your pump should prime, then the relay clicks it off when the pressure has been reached. If it still pumps then the pressure is lower than the regulators setting and the relay kicks the pump in again. Try clamping off the return line to see if this improves the running.
Some points: 1/ when the engine is stopped oil pressure drops immediately 2/ even if oil pressure stayed high the pump cannot work as it operates on ignition switched power. (ignition is off) 3/ the fuel pressure regulator does not turn the fuel pump on/off as it has no electrical connection 4/ I think the way starting the car works is first you turn the key to IGN and the fuel pump primes for a second then turns off (via a timer), engine cranks, starts, oil pressure immediately rises and oil pressure switch closes and now supplies power to fuel pump. If you have low oil pressure the engine will stop because no power is going to the fuel pump....same as if you have a prang and the car ends upside down - no oil pressure so no fuel pump which is pumping fuel onto a hot engine and you! 5/ the above is basically guesswork but its the way I figure it. Apart from the above I'd be checking the fuel pressure regulator as others have suggested espescially the vacuum feed to it (no vacuum = no fuel regulation)
yeah, i am only a newbie tho and dont have my p's yet so i dont drive my car to work yet, i had a discussion with one of the lads and he diagnosed it as a dribbling injector and could also be leaking to hence why my plenum chamber is covered in crap and reaks of fuel, he said the vs he had never got dirty inside the plenum, so the guys at tafe said i can take the injectors in and have them cleaned (part of the course so thats handy)
should have written that better, i had the fuel pump going with the terminals in the relay connector bridged, or as gregories say 'diagnostics mode' for checking fuel leaks, but yea im a bit sus with the regulator
am getting my diff fixed on Monday with the help of my dads mechanic so ill see how i go, he might have a few tools to help further diagnose it but yea thanks guys for your help really appreciate you giving your time, will have a write up when i find out what it is
well my problems is gone and ive never seen my car go like it is now, the problem, injectors, they were so grotty, i had: 5 leaking (3 were flowing others were dripping) 3 dribbling is that a record? lol
nothing, it was part of my tafe class and i was lucky enough to get them tested and cleaned all i did was pay for the filters, o rings, pintle caps
ok i spoke to soon, my hesitation is back and with a vengance, the day i put my car back together it was perfect and i couldnt be happier, now, two days after its coughing and splutter, and yesterday just before it started to rev it made a metallic 'ting' noise which appeared to be from the rear of the engine, at tafe today we hooked the diagnostic machine up to it and cleared all of the abs faults and the ecu's 'history faults' and did a few diagnostics test which it all passed, the only thing the teacher could say for the 'ting noise' was its pretty common for the torque convertor bolts to come loose and as the metals warmed up it became all tight again so to speak so once again, im asking for help if anyone has expiranced this problem or know of anyone who has please, please, please give me some more ideas, just some ideas to note, seems to have a little loss of power under 2.5k revs, idles a little ruff and sometimes revs allitle low in gear, like 1to2mm above the small line above the 0 mark on the tacho all leads are new, tested and are fine, new plugs, new fuel filter, pressure regulator appears to be not leaking under vacuum injectors have been cleaned, flow tested etc, clean, plenum, throttle body and new/second hand iac valve, thanks for your time, and please chuck some more ideas up for me
