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92 740T will start fine once, then sputters out and will not restart and stay running

THe little hose to the blow off valve that runs to the intake manifold? No it's the big hose usually collapses when it gets soft. If you got new ones then probably isn't your problem.
 
Not the hose from bov, the one connecting from that nipple on the intake tube from AMM. I think its the PCV hose? If that isn't it, I will continue on with the o2 sensor then. That is seeming to be the biggest possibility with it having failed at rich readings anywho.
 
No, it's the intake tube from the airbox to the turbo that collapses. The stock ones get oil soaked from the PCV and age and turn into gooey, limp hose-like things and under vacuum (ie when the turbo is pulling in a bunch of air to compress) they collapse which starves the engine. If you have a newer silicone one, that is not your problem.

The PCV hose won't collapse and even if it did it wouldn't be a problem in the way that the intake hose collapsing would. Your problem is elsewhere.
 
ortho stice said:
No, it's the intake tube from the airbox to the turbo that collapses. The stock ones get oil soaked from the PCV and age and turn into gooey, limp hose-like things and under vacuum (ie when the turbo is pulling in a bunch of air to compress) they collapse which starves the engine. If you have a newer silicone one, that is not your problem.

The PCV hose won't collapse and even if it did it wouldn't be a problem in the way that the intake hose collapsing would. Your problem is elsewhere.
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Quick question, when I was testing injectors after having them flow tested the resistor pack had broken during operation. Could that breaking have caused power spikes to the injectors, potentially enough to fry one? I am still getting intermittent blips in throttle after unplugging the o2 sensor, so just checking before I replace another broken part that won't solve the issue.
 
I guess that depends on what you mean by broke; it really is just a pack of resistors. Usually when a resistor goes bad it goes open circuit which would mean no injector pulse at all.
 
replaced pack completely. I got it out on a test drive yesterday. When coming to a stop if I let off gas, when trying to move again it would want to die but if I kept my foot on the pedal, it drove around relatively ok, other than when going up a hill it almost refused to shift into 1st gear from 2nd, to the point where it felt like it was going to die. When I got the car back to the house, the oil sending line to the turbo looked like it was starting to leak at the turbo, and the turbo was smoking off the oil. I pulled the intake to the turbo and vanes look good, no in or out play and no real up or down. It did seem very rich as every time I would let off the throttle while rolling above 2k, it would pop, which it did somewhat beforehand, but not to this amount.
 
At this point do you have known good coolant temp sensor, Maf, and o2 sensor? Is your throttle set according to spec? Is your kickdown cable set to spec?
 
Crustacean Wagon said:
At this point do you have known good coolant temp sensor, Maf, and o2 sensor? Is your throttle set according to spec? Is your kickdown cable set to spec?
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Brand new ECT sensor and MAF, but O2 sensor is still on order. Not sure if bosch is on back order or what. I believe kickdown cable is set, but honestly might be a good place to check again.
 
Seriously, do it and report back. People love to pull out the credit card and fire the parts cannon. Might as well pull out the credit card and load up with diagnostic tools instead!
 
Update time! New o2 sensor in cleaned up the idle, seems to sit comfortably in idle. Still noticed weird bog at initial throttle, and could still kill engine if i bounced the throttle. plug wires were messy so went to adjust and shocked the piss out of myself, so put some spark plug separators to see if that would clean up any interference between the wires. Seems to take throttle a little stronger, but I can still kill it by bouncing the throttle. Going to reach out to a buddy with a smoke machine (finally) and check for air leaks, but it does feel a lot better. Could it possibly be blowing out spark due to not great plug wires? Assuming they shouldn't be able to shock me through the sheathing, but then again could be wrong and dumb.

Also, wonder if the throttle may need to be adjusted? I feel the click where I am supposed to I think, but is there any afr adjustments on throttle body? Thinking it could have been adjusted before having the fuel system repaired, and now that it is getting the correct setup to the rail, could it be pushing more fuel than needed, or vice versa?
 
No adjustments on throttle body with LH2.4. In closed loop it's MAF and O2 only. If you haven't disconnected the battery since you've started to get improvements, it's a good time. The ECU will have been trying to compensate for shortcomings and you can give it a hand by disconnecting the battery for a couple minutes to reset adaptations.
 
baddecisionsmadedaily said:
Update time! New o2 sensor in cleaned up the idle, seems to sit comfortably in idle. Still noticed weird bog at initial throttle, and could still kill engine if i bounced the throttle. plug wires were messy so went to adjust and shocked the piss out of myself, so put some spark plug separators to see if that would clean up any interference between the wires. Seems to take throttle a little stronger, but I can still kill it by bouncing the throttle. Going to reach out to a buddy with a smoke machine (finally) and check for air leaks, but it does feel a lot better. Could it possibly be blowing out spark due to not great plug wires? Assuming they shouldn't be able to shock me through the sheathing, but then again could be wrong and dumb.

Also, wonder if the throttle may need to be adjusted? I feel the click where I am supposed to I think, but is there any afr adjustments on throttle body? Thinking it could have been adjusted before having the fuel system repaired, and now that it is getting the correct setup to the rail, could it be pushing more fuel than needed, or vice versa?
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If you are getting shocked by the plug wires it is definitely time to replace them.
 
2manyturbos said:
If you are getting shocked by the plug wires it is definitely time to replace them.
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Thats kinda where my mind was. If it is letting out like that, I can only imagine that it's not getting what it should at the plug. Planning on grabbing a set of NTK or NGK, whatever brand it is, wires and seeing if that helps out. Seen a few forums stating they were a good set similar to the bougicords, but I guess we will see. I have disconnected the battery most nights to prevent drain so should be good on that side, but I do wonder if it needs to run through a drive cycle to fully relearn everything.
 
Very delayed update but after replacing the spark plug wires with quality set, car is running enough to get around town and such! Did find out today though that my electric cooling fans don't seem to be kicking on, and the turbo seems like its not getting proper oil flow and smokes a slight bit after a few miles of driving. Lastly, I also hear a slight high pitch whine or whistle, not the turbo boosting but goes with it, when I am under load. Going to check fuses and relays for fans, but any ideas on the turbo stuff?
 
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