5.7L TBI stalling and low idle help

[thinger2]

Yes but a scanner will tell him how well the other parts are playing with other parts . There could be a possibility that one part is on the verge of becoming bad that could cause another part to act up.

I would normally completely agree but I dont know if hes quite ready for the learning curve of live data yet.
Probably needs to start with some fundimentals first

 

[smdk2500]

I would normally completely agree but I dont know if hes quite ready for the learning curve of live data yet.
Probably needs to start with some fundimentals first

That is true and I'm not saying that Im the worlds greatest at reading live data but with getting the data he could post it and have more experienced people read it and advise. Doing it that way he could learn and it would help others like me learn as well.

 

[thinger2]

That is true and I'm not saying that Im the worlds greatest at reading live data but with getting the data he could post it and have more experienced people read it and advise. Doing it that way he could learn and it would help others like me learn as well.

I get it but hes got OBD1 so the scanner he needs to get any usefull data is kinda spendy

 

[smdk2500]

I get it but hes got OBD1 so the scanner he needs to get any usefull data is kinda spendy

That is true as well. I

 

[James Archer]

Thanks everyone for the advice! I really appreciate it. The parts I put it I wanted to replace either way due to the truck being 30 years old. The previous owner said that the motor was swapped at one point. I did the error code reading and got 33. Which comes up as MAP low vaccum

 

[James Archer]

Finally figured somethings out. Got the exhaust temporary on. No more EVAP leak code but now I'm throwing a Code 42. Any suggestions on where to start with this? So far it runs perfect besides at low idle. It hiccups then takes off
Ignition Bypass Circuit Error

 

[PlayingWithTBI]

I had a code 42 last year, it turned out to be my fairly new (~2000 miles) cheap a$$ Spectra Premium ICM.
https://www.freeautomechanic.com/gm-code-42-electronic-spark-timing-or-bypass-fault.html

Replaced it with an AC Delco one and never looked back.
https://www.summitracing.com/parts/ado-d1984a/year/1988/make/chevrolet/model/c1500

And used plenty of thermal paste
https://www.amazon.com/ARCTIC-MX-4-...jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

 

[Jeff5may]

Yup, distributor with electronic module is a common thing with the TBI vehicles. Last week I amazed a good friend by resurrecting his v6 Silverado. Same random behavior as yours. His wasn't as far gone as yours, it would usually start up good in the morning. Once it warmed up a bit, no bueno.

I took a look under the hood and immediately saw a shiny aluminum distributor. Checked the timing: good in disabled mode at zero, all over the place in electronic control mode. I went home, grabbed the distributor out of the S10, and brought it to his truck. Pulled his cap, noted the rotor position, and swapped my 30 year old dirty Delco distributor. Put his cap back on my old guts, turned the key, and set zero in disabled mode.

He took his shiny durodone distributor back to advance zone and got a spare, in case my old OEM ever dies. After he tried to give me a hug and a kiss.

 

[PlayingWithTBI]

Checked the timing: good in disabled mode at zero, all over the place in electronic control mode

Yeah, I caught mine while data logging cruising at ~2000RPM while it was surging, finally trapped the RPM at ~4775RPM (impossible). What happened was the ICM sent false pulses to the ECM which, in turn, sent different timing and fuel, based on higher RPM, momentarily to cause the stumble/surge.

You must be registered for see images attach

 

[PlayingWithTBI]

Oh BTW, this is with TunerPro RT, an ALDL cable, and my laptop - total cost = ~$60, less the laptop, LOL.