87 chevy r20 code 44 please help

[78BIG-TEN]

Yes there should be 2 senders\switches,and one will run the fuel pump in case of relay failure.Backfire through throttle body tells me to lean or timing way off

[cditeodoro]

I know the timing is good. I had to replace master cylinder about a month ago. Is it possible my booster is causing a vacuum leak? My breaks seem fine though.

[VileZambonie]

You're sure you don't have #5 and #7 ignition wires reversed?

[VileZambonie]

Oh and the oil pressure gauge has no factor in it.

[cditeodoro]

I'll check plug wires in the am to make sure they are right. I'm also going to check booster for vac leaks

[cditeodoro]

Well checked plug wires and they were where they were suppose to be. Plugged booster line to see if it had a vac leak and truck still runs poop. Whatever the computer reads in open loop is the suspect because when it's first started and in closed loop it doesn't stumble real bad and has smooth throttle response.

[VileZambonie]

How does it run if you unplug the engine coolant temp sensor? (Keep in mind this will set a DTC)

[Irish_Alley]

 check your wires to the o2 sensor make sure they are not rubbed or pinched anywhere. the o2 sensor does kick in about a minute after start up

Ground in wire to ECM terminal 9 or Open in wire to ECM terminal 14.

Code 44- This code will be set whenever the ecm perceives a lean exhaust condition. The main causes for this is a grounded O2 sensor, low fuel pressure, restricted injectors, contaminated fuel, exhaust leaks or bad air switching valve. The condition met to set the code is  a low  O2output voltage (less than 0.2V)around a minute with the ecm is closed loop.

[cditeodoro]

It runs better when the cts is unplugged. My o2 wire looks good and it hasn't thrown the lean code since I got the leak fixed.  My driver side exhaust manifold touches the frame on the truck because manifolds are off a newer truck. Could that have anything to do with it? Basically when I first start it in the morning I can smack the throttle real quick while in park and it revs great, no stumble, no pop. Then after about 3 min of running great it's like somebody turned the switch and it runs bad, searches at idle and if I smack the throttle it will pop out the throttle body or just bog. It will run like that until the temp gets up and slowly run better. Once the temp is up I can blast on it and no popping out of tbi but power is not what it's supposed to be at all and the idle seems lower than normal in gear, and it will still do weird stuff sometimes at idle almost like it skips a beat if that makes any sense. So I'm not sure why it gets better as it gets hotter. I was thinkin maybe I missed a ground so ewhere when putting the new motor in. I have one from battery to head on pass side and frame to battery and firewall to head on pass side and cts is grounded to intake and I have a ground by the distributor that is bolted to intake. Am I missing one ?

[cditeodoro]

Sorry but you guys loose me when you talk about ecm grounds and stuff. I've looked at my ecm up under the dash but that's as far as I got because I don't have a clue. Is there a ecm ground somewhere that I should check?

[78BIG-TEN]

ECM grounds should be at either 2nd bolt\stud from front on pass side of intake or at drivers side of t\stat housing bolt\stud.Check them with engine running with a volt meter positive lead to ground wire and negative lead to negative battery post,should be less than 1\2 volt

[cditeodoro]

Well I give up!  I just saw the regulator housing is cracked probably from ovrrtighting after I rebuilt tbi so maybe the guy in Harrington wants to buy it cheap.

[Irish_Alley]

what regulator? fuel pressure?

[cditeodoro]

Yes. Still runs but that's it for me I'm not putting another dime in the truck

[roundhouse]

Check the fuel pressure

If your unplug the o2 and cts and drive it
Does it run ok?

If so just leave em unplugged

Or try plugging em in to a sensor that's just Laying on top of the motor