Discussion
PetrolHeadPete said:
2.2 ish. See below. This was idle, to fast idle, to idle. Starts at 950, up to 1500, then back to 950. Dark red trace near the bottom (v hard to see)
I don't know specifically about your car, but injection duration of 2.2ms would appear very short, and would suggest the ECU is trying hard to lean things out. And succeeding. So the ECU imputs that effect fueling are suspect. Engine MAP, AFM, TPS etc, but the main one I would look at is the Lambda. What would happen to the injection pulses with a disconnected Lambda? 
Just my thoughts.
Cheers
Hi sounds like mine after my engine rebuild, I removed the throttle bodies and resealad , balanced them as per manual,new Lamdas use the speed six ones from tvr parts they will last longer (had new rover ones in jooles put tvr one back in as rover was not keeping up !!) then take it to jooles to map (best thing I did with the car)
Injectors made no difference. I fitted Lucas D1720AB types which race Tech list for the 4.0. The originals are D1000AB which they only list for the 3.6 very odd. Anyway it runs albeit adaptives are trying lean it out on both banks so I suspect these are the higher flow injectors. But either which way...it still misfires exactly the same. Also does the same with lambdas unplugged. Next check is cam timing...could it have slipped. It's the only mech thing left to check that I can think of. BTW, stethoscope on each cylinder they all sound the same. None have any obvious stumbles etc.
The one at the point of problem starting was brand new as of perhaps 2 years ago when I was trying to improve shunting. It made no difference at all. The one I tried this time round was the original, hence pretty confident its ok. My buddy is convinced its electrical having experienced it. Running on 5 cyls...how rough is it ? I would guess not *that* bad, just a bit rough but still quite a bit of go ? When I'm in the "zone", modest extra throttle makes almost no extra accel, it just gets noisier, shakes more, until you plant you foot and off it goes (couldn't guarantee there isn't still a misfire in the background, but it certainly gets most of its power back). His theory goes that anything mechanical will get worse at load and speed, and I think I take his point.
What was the outcome of spraying the bodies for leaks.
Like your mate is saying. This sounds electrical, the system is very simple. I’d be very tempted to replace the HT side of things with new.
Annoyingly I’ve just taken leads and a coil to the tip as I’m moving and clearing out, which I could have sent you.
Like your mate is saying. This sounds electrical, the system is very simple. I’d be very tempted to replace the HT side of things with new.
Annoyingly I’ve just taken leads and a coil to the tip as I’m moving and clearing out, which I could have sent you.
Not much left to check.
I assume battery/generator voltage is fine when fault occurs ?
I think its worth to check the splicing of the injector loom nevertheless you checked voltage at the plugs.
It all seems temperatur related.
Finally it could be a faulty ECU. Maybe you have a mate with a spare to swap ?
I assume battery/generator voltage is fine when fault occurs ?
I think its worth to check the splicing of the injector loom nevertheless you checked voltage at the plugs.
It all seems temperatur related.
Finally it could be a faulty ECU. Maybe you have a mate with a spare to swap ?
It's all back together with the original injectors now ready to start some buzzing out.
Interesting that after a short drive with the new injectors...all plugs look pristine but 6 is pretty sooty. Guess the ecu can't lean it out enough with those injectors. But strange that 4 and 5 look perfect! How could 6 be different unless it's missing some spark.
Interesting that after a short drive with the new injectors...all plugs look pristine but 6 is pretty sooty. Guess the ecu can't lean it out enough with those injectors. But strange that 4 and 5 look perfect! How could 6 be different unless it's missing some spark.
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