GM 5.7 TBI rough idle and stalls out when put in gear ?

1995 GMC Suburban 2500 4x4 with GM 5.7 TBI motor and automatic transmission.
We have...Installed a new exhaust system from the catalytic converter back, instaled a new o2 sensor, MAP sensor, engine temperature coolant sensor, new fuel filter as well as new fuel lines from the TBI down to the frame rail where the fuel filter is located. Both, the supply and return line were replaced from this location.
(((Sorry for the door buzzer beep!)))
The motor will start up fine, cold or warm. When starting from cold, the it will be in the high idle mode, apprx. 1000 RPM. Once at operating temperature, the RPM's will drop to around 800. When you put your foot on the brake, the RPM's will drop and as you pull it into gear, either drive or reverse, the motor will die. The motor will start back up again, but this issue is consistent. Also, at temperature, if you give the motor more throttle, there is a noticeble miss / rough running condition above 1500 RPMs.
There does not appear to be any vacuum leaks and the EGR valve appears to be functioning correctly. The TBI's appear to be spraying a cone fuel pattern without any drips.
I am not able to check the inline fuel pressue due to no valve on this series of fuel lines.
Please comment with your thoughts and suggestions on where ot look next for a possable fix.
Thank you.

[@lunalancer5971]

Had an idle / shifting into gear issue similar to yours. Replaced the EGR valve Fuel filter plugs wires, then the cap and rotor like you said. Disconnected the battery to hard reset the computer and drove her around a bit now she idles great. Still has an issue with hard/late shifting and accelerating weird, but doesnt die anymore fingers crosses. Cheers bud

[@johnking9840]

Again your transmission is electronic so the wires that run through that plastic loom I talked about is hot wires. If it's melted to exhaust then the hot grounds out alot in computer. You'll have to reset it every time. Mine is a 1994 I put 5.7 t bi out of k15 blazer and got to were it wouldn't come out of second gear sometime just first. I found the bad hot wire in loom and now runs great

[@LeeGoodFella007]

@@johnking9840where about does it usually melt to exhaust?

[@LeeGoodFella007]

IAC can cause improper shifting

[@smknjeephandsawcreek2021]

The door should be closed... That buzzer was hard to handle

[@duginvirginia5737]

Ha...yeah...it was. Corrected that in the follow-up video !

[@ciskolse-forty699]

I just fixed mine for emissions, I found out the distributor was bad. Replace it with a cardone brand new distributor now it’s good to go.

[@darthrevan82ta23]

Also maybe related to transmission, if the TCC is not disengaged properly, it will cause the motor to stall while in gear at a stop

[@anthonybaeza2215]

When you woudl sometimes take off & engine rmps are high did it ever make a pop ? Or run a tap rich ?

[@duginvirginia5737]

Hello, we will do a follow-up video soon. We picked up a Snap-On computer of the same vintage and ran throught some tests. The RPMs were actually showing in spec, but the O2 would often witch between normal and rich. We also need to put a timing light on it and see how it is looking. More to come. Thank you.

[@Paul-fq4mm]

Just bought a 1999 f150 5.4. I have a similar situation. When my truck has been off all night and I first crank it in the morning it doesn't shake or anything. Once I drive it a little bit will start shaking when I'm stopped or parked. The rpms don't move around to much stays about 1000rpms. Seems to get quieter when in neutral. Changes throttle position sensor, plugs and coils, air idol control valve and pcv valve and it's done nothing to fix the problem. Check engine light is on. When I'm over 40mps and accelerated it doesn't vibrate or shake or surge. I also recently had a couple times I went to start it and it would crank first couple times almost like a dead battery but then third time started right up. So, lost at this point lol

[@duginvirginia5737]

Very frustrating for sure. Regarding the check engine light, did it show any codes that lead you to replacing the listed parts? If so, with everything new, it's even more frustrating. Did you check the Oxygen sensors in the exhaust? Also, on your truck, is there a sensor in the air intake? I recall my brother had an issue with one of his mid to late 1990's Ford trucks and it ended up being the tube between the air cleaner and intake had a sensor and I don't recall if it had been disconnected or the tube was loose between the air cleaner and intake, but that sensor in that line was giving a false reading of no / inadequate air supply and the motor ran very rough.

[@henryh2249]

It's the throttle body position sensor on the throttle body. The little copper tips in censor move up and down as the engine gets hot or are burned or or out and it can't find the proper

[@videosrfun4me189]

So, its been 2 years, did you find an answer for it stalling when you put it in gear??? do you have an update>

[@duginvirginia5737]

In my case, there were two issues...first was the secondary ground wire, which i did cover in another video, but its the ground that runs from the firewall to the frame and then from the frame, through the wire loom at the starter and then on to the back side of the bellhousing. The other issue, and biggest contributor to the problem was a bad distrubutor cap and rotor of all things. The button in the center of the cap was badly worn and almost powder! We replaced the cap and rotor and that solved the problem! Very stange, but that was it. Since this vehicle was used when we got it, there were a lot of probmes we were chasing down. Thank you for the comment and interest.

[@videosrfun4me189]

@@duginvirginia5737 i will check my grounds. my truck has not left the yard in 3 years. it dies when you put it into any gear or when activate the tommy lift causing a load. every mechanic I know have no answers. the alternator voltages seem fine, I have replaced every sensor under the hood, cap and rotor, fuel pump and filter and still no change. i also had the head gasket replaced for a small leak off cyl5 .$1600 later it still dies. anyone else out there have an overlooked possibility???

[@LeeGoodFella007]

It’s so annoying that this happens but I put in a brand new temp sensor, had the idle issue, ended up finding a used temp sensor put it on, and my idle was fine

[@duginvirginia5737]

My issue turned out to be a very worn cap and rotor,

[@AntiqueCarsandStuff]

Just a couple of comments; we had a similar issue with our Honda Pilot a few months ago. Turned out one of the ignition coils had failed. That’s all it was. It took a shop to diagnose it because I don’t have the diagnostic tools. Another thing, does the oil pressure seem high? Probably not related to the issue but I wanted to mention it. Anyway, good luck. That’s a tough one to figure out!

[@duginvirginia5737]

Thank you...I keep scratching my head on this one...lots of research, try a new sensor, etc. and still same condition. I'm in the same boat, no diagnotic tools and for me, trying to rule out the easy stuff first before committing to a shop. Regarding the oil pressure, yes, that is another issue I need to address; from what I've found out so far, it's either a faulty sending unit or a bad motor on the back side of the gauge. I want to do an oil change and see what it does with fresh oil, this is a new to us vehicle so thankfully it's not our every-day driver.

[@duginvirginia5737]

So, the idle issue is still a puzzle, however, after changing the oil and filter, the oil pressure is at a more respectable 60 psi after the motor has warmed up. Draining the catch pan, I’ve no idea what viscosity the previous owner used as it was black as coal and definitely not 10w-30 !

[@AntiqueCarsandStuff]

@@duginvirginia5737 good, that’s one problem to check off the list!

[@dannygee4562]

98 dodge 1500 4x4 ... is was my cam position sensor.

[@boshhutchings8145]

I just bought a 93 with the 350 tbi and I had the same symptoms..I replaced the whole distributor and she burns rubber now with 300k

[@paralegalparaplegic8177]

I have a 92 has a rough idle in gear like 200rpm still make it burn rubber Still trynna fix it tho 💀

[@matthewgraham2129]

@@paralegalparaplegic8177 did you ever figure it out?

[@paralegalparaplegic8177]

@@matthewgraham2129 no but soon I'm going to buy a dso and obd2 scanner and see if there's any faults/ codes in my situation i think i just have my idle air control valve set too low havent bothered to adjust it though

[@paralegalparaplegic8177]

@@matthewgraham2129 seeing toher comments say they fixed their issues its definitely a problem on the ignition side

[@bjohnson5521]

My 89 caprice tbi runs in park but when put into gear it dies if I don't give it gas

[@duginvirginia5737]

I'd check the cap and rotor first and then go from there.

[@BroiBoLs]

Idle control senor next to the throttle body?

[@duginvirginia5737]

Thank you...It ended up being the cap and rotor !

[@BuySellTrade-g7i]

Cap and rotor ? What is that exactly?

[@duginvirginia5737]

@@BuySellTrade-g7i Distributor Cap and Rotor; inside the distributor.

[@davidgates1887]

Oh ok thanks but I thought it might be the idle control sensor but nice to know I’ve got a Buick to look at this spring!

[@johnking9840]

The factory ran wires running from starter to coil and battery and oil sending unit and there ran through a black plastic loom and their burnt against manifold

[@duginvirginia5737]

Thank you. I will check for and inspect that.

[@johnking9840]

If you look down beside passenger side manifold you should be able to see it brittle and burned. Plus you have a braided ground with three ends one goes to frame engine and body. If that is broke then the electronic transmission and everything else will mess with computer

[@duginvirginia5737]

@@johnking9840 Thank you...I will defintely inspect that ground wire as well. Many thanks.

[@duginvirginia5737]

@@johnking9840 Thank you...Looking for your thoughts on this...I did have the ground wire issue as you had mentioned. The braided copper wire from the firewall to frame was ok, hovever, the one from the frame to the top / back side of the bell housing was broken. I tried to replace that one, however, accessing, let alone seeing the bolt where it attaches just wasn't happening. So, I added an new ground from the firewall to frame, using the same firewall mounting bolt and using the frame bolt that holds the rear heater hose bracket and from the frame to the bottom of the bell housing; using a bolt that was readily accessible that joins the motor and transmission. Despite this new ground not being in the exact same location on the bell housing, I'm assuming it will do its job. Fingers crossed ! THe wire that you mentioned, tends to be melted by the manifold, what does that wire / wires go to? I want ot ensure everything else is OK.

[@johnking9840]

The wires coming off the starter going to IGN and alternator but thoughts wires run through a plastic loom is what I call it. Supposed to be heat safe and won't melt but they do. The factory did this to all the Chevy truck sometimes they will have it running through a pipe that looks like piece of exhaust but is only 5 inches long. Promise the wires inside that look is bad

[@bodhimack]

Why is your oil pressure so high? Too much oil could cause too much pressure and cause a stall under load...

[@duginvirginia5737]

Initially, I do not know what oil the former owner was using or how old it was. We did an oil change with the correct oil weight as well as a GM filter and the oil pressure now runs around 60 PSI unless a hard acceleration occurs and it will bump up some and then go back to 60.

[@cadequattlebaum3157]

What did it end up being I’m having same issues

[@duginvirginia5737]

The short answer is it needed a new distributor cap and rotor. Replacing those two items corrected the issue.

[@the1whoknocks275]

@@duginvirginia5737 what is the long answer? Lol

[@hernandezstudios]

@@the1whoknocks275 did you fix your issue? I’m having the same problem. Thanks

I have that same issue too but i have change the 3 coil pack, spark plug, egr delete and still have the same issue.

[@hernandezstudios]

@ I Fixed mine, It ended up being the pressure regulator on the throttle body injection.

[@fredwicker5400]

Try cleaning the throttle body, do not use carb cleaner. Should not be any black varnish present. Check throttle position sensor. Make sure crank sensor is clean. Check fuel pressure. That's my shade tree guess.

[@duginvirginia5737]

Thank you..I'll continue to check on those items. Always seems to be sometihng to get in the way or working on a fun project !

[@davidrussell9992]

Spray some throttle body cleaner in there and wipe with a rag it’s not opening and shutting causing it to die or surge

[@duginvirginia5737]

Thank you...I'll follow up with this and see how it works.

[@davidrussell9992]

@@duginvirginia5737 what’s up? Did you fire it up and drive it around your block like your hairs on fire?

[@kimberlystern6677]

Send Scott a message and see what he thinks.

[@rodneyleduc4833]

It's neutral safety switch

[@craighatfield6391]

Vacuum league

[@brian7189]

Seek Jesus! Repent for the Kingdom is at hand! Jesus is the way! The truth! And the life! He’s the ONLY way! Open the Bible, read and understand that we are in the last days! Put your full trust in him! Believe 1 Corinthians 15 1-4!

[@jadenhall3570]

Amen!

[@SteveV74]

Will Jesus fix the rough Idle?

[@AllGoodOutside]

Wow we've been in the last days since somebody wrote that in scrolls over 2,000 years ago! I figure we got a few more days to fix a rough idle and decide on which omnipotent being to pray to and which one is best at vehicle repairs and takes requests😊

[@tylerganieany6386]

I hope so bro

[@jamespate7066]

Egr valve

[@duginvirginia5737]

Thank you. I had pulled the EGR valve and ran a test on it and appeared to test OK / work. Do you suggest a replacement anyways? ...Possiblely weak or slow to react?