94 sierra tbi 350 hard start and stumble problem i think when cold

Hi guys i have a 94 gmc sierra 350 tbi and i have like a little hard start problems when cold but in this video start well... but not so cold in this video like -8 but when its -15 or more it craink like 2,3 more time and have a poor fuel economy some time and poor acceleration i change all plugs AC DELCO and wires rotor and cap and i go to a mecanic to set the timming of the truck after doing that is that a vaccum problem ?? and the truck loop when cold ... is that a faulty catalyc converter ? do a poor start and make the truck looop please i need advises thank you oh and sorry i touch a botton on my phone and shut down the video quickly .. PS:Love GM trucks long live chevy's

[@royalsaint117]

My chevy has hard starts and it's a 93 350 v8 5.7 I notice your thermostat gauge gets power but doesn't read anything. Replace coolant temp sensor cause these trucks are known to flood the engine creating a very rich mixture of gas upon start and rough idle ect. Hear model trucks are made to operate with oil pressure as low as 8-10 PSI as long as your oil pressure switch doesn't turn your engine off it's fine. As for the acceleration like mentioned below replace fuel filter and add a quarter of a bottle of sea foam in your gas tank to clean fuel lines and injectors

[@devinkempa4851]

if you havnt replaced your engine/coolant temp sensor replace that also.

[@jslangager]

I had a similar problem with my 1992 but I replaced the fuel filter an that made a big difference. You should try that because its cheap and easy to do. Especially if itd been awile.

[@ARichardson4310]

My boss changes his fuel filters every year, he owns a lamdscape company

[@SuperchargedPathfinder]

I am running into the same issue. It feels like it is running on 3 cylinders then clears up and runs great. Some days it has all the power in world while others it seems a bit off. My hard start can happen when the engine is warm too. I am looking into it.

[@gobabygo48]

Ever figure it out?

[@nicholaselias2946]

Seems fine, though the voltage was a little low for when starting. My truck does this ('94 Sierra 5.7) whenever I basically start it. Check the terminals on the battery, if not bare metal then the starter isnt getting enough power. If thats not it, tighten the battery terminals down snug, could just be loose

[@eddiej218]

Hi @Mathieu Levesque, I was having the same exact issues that your truck was having. I'm driving a 89 Chevy 1500 Ext. Can with long bed running a 350 5.7 with a 700r4. I changed the battery, starter cable, terminals, spark plugs, & wires, & cleaned my TBI & fuel injectors. My truck was getting horrible gas mileage. I live in Louisiana & when it would get around 50 or below it would have trouble turning over. Pretty much taking me more than one try to turn the block over along with pressing the gas paddle down for more throttle. Once the block is warm or on warmer days it would crank on the first try with ease. I recently spoke with my dad, the one who owned the truck before me about him having any issues with it performing like it was & his answer was to my surprise no but he gave me a bit of info that I never thought about. He suggested that I change the MAP Sensor. I had never changed that particular sensor nor knew what it was until he showed me. It ran me about $50 here in the US but it was indeed the problem. I haven't had an issue since. I don't know if you discovered this as well or just fixed the issue because of how old this video is but hey give it try. Btw, also try changing the electronic spark module

[@TheUndertoe]

These motors hate the cold so as long as you have no issues when it’s warm don’t worry about it mine does that it even pops for a bit

[@davoid2006]

Ill agree with "Fives"... check all grounds especially the ones on the thermostat housing bolt. unplug the est connection for the timing and see if it starts faster if so then pickup coil needs replaced. Also clean IAC valve. (CTS) coolant temp sensor next to thermostat housing is also a culprit of hard starts and/or rough idle.. check intake for leak by using brake clean... itll UP idle if intake is leaking. - DTM

[@davoid2006]

After starting a valve cover and gasket job, I found that I had "milky oil" on my dipstick... uh oh!! The truck was NOT overheating nor NEAR overheating at all. Well.. when it was all said and done while taking all the sensors and accessories off the pass side I broke off the "quick disconnect" heater hose from the pass side rear of intake. I broke it off FLUSH with the intake so ...I wasnt about to drill that out so I made a quick text a to a friend who actually just happen to have a "clean" TBI intake laying on the floor of his garage. So yeah, I replaced the intake and gaskets with a new one, which it was going to get done eventually so...When uninstalling the old intake, I found what I was looking to see... coolant in the "lifter gallery". I think I caught this just in time becozz their was NO coolant in the oil or oil filter after letting it drain for 1 entire day and overnight. Either way, to flush out any that may have been in the oil or pan I got 1 gallon of deisel fuel and just flushed the engine out.... pouring it in both sides of valve covers and watching it come out the drain plug. No coolant. So I think I got this issue JUST in time!! Lets see... new intake, gaskets, valve covers, gaskets, new EGR

[@davoid2006]

Id have to come to a conclusion that I was having an oil leakage problem with intake which caused coolant leakage into the lifter gallery over a period of time which further cause "vacuum" leakage of some sort... Im just speculating at this time becoz I dont know for sure IF my "choke mode" problem is solved or not til I put more miles on this "refresh" as I call it. I will go back and say that before I started this "job", I did replace the IAC valve on the TBI and this did NOT solve my "Choke Mode" issue so... IDK... speculation thats all.. Ive tried it all. so IF further issues, I will keep posted... thanks... wink... - DTM

[@telorvehc0chevrolet]

Set timing under the following conditions: * Normal operating temperature. * Air cleaner installed. * A/C "OFF." * Transmission in neutral. * Disconnect SET TIMING connector with engine off. (Esc connection) Connection is probably under your glove box. Single brown wire with black stripe I think. This must be unhooked to set the timing. It keeps the computer from controlling the timing while you're adjusting it. Search for timing a 350 tbi on youtube. Itll take you through the basics

[@barrygordon1173]

Air cleaner has to be removed...never get to distributor....transmission in park same as neutral...

[@WS6xMASTER]

I am having the EXACT same issue. Down to the last detail. i have replaced a but load of sensors. i have grounded the intake ground wires to the block. i have replaced a but load of stuff fuel filter. i rebuilt the throttle body. i have EVERY sensor is new. the truck still does this weird stuff.

[@WS6xMASTER]

its a 93.

[@devinkempa4851]

SIMPLYBEAST1231 its a fuel injector

[@WS6xMASTER]

Devin Kempa i will replace them now.

[@devinkempa4851]

i would replace the engine coolant temp sensor first before you mess with the injectors so dont replace injectors first. go for the engine temp sensor. trust me .

[@devinkempa4851]

the temp sensor reads colder than it should this sending a signal to the DME unit to provide richer fuel. when it starts to fail, it sends a higher than actual temp signal to the dme unit. then the dme unit leans the fuel mixture thinking the engine is at normal operating temperature. this causes the engine to run rough. as the engine warms it no longer needs the richer cold idle so it runs smoother afterwards.

[@geezusmeatball1328]

i change all that ... fuel filter clean the carb with new fuel pressure reg with diaphragm, new spring in it delete the Cat now straight pipe with muffle behind, the egr working good its maybe the coolant temps sensor ... but its new since 3 years now . maybe i need one new .. and whats is the Est ? connection ?..

[@JDL0111]

dude I like your truck

[@slaggweldgod]

I have the same issue with my '94 C2500....... a friend suggested that it might be an ignition module.....mine backfires in through the throttle body.....I told him that, and he said that it may not be giving the computer base timing, so the computer isn't advancing the timing on acceleration.

[@WS6xMASTER]

slaggweldgod sounds like a warn timing chain

[@calvinharris8712]

How did u fix ur problem I have same issue

[@fredrickcollins9432]

how did you fix you problem mine is doing the same thing

[@geezusmeatball1328]

Is my Catalyc is the problem of my hard start and performance problem ?? or vaccume lines is the problem of the strumble ?

[@geezusmeatball1328]

thank you i think its my cat converter because i remove my carb and cut the little ridges and clean all my carb and i remove the fuel pressure regulator and clean it and put a new Fuel Pressure Regulator Diaphragm with gasket and change nothing maybe its the fuel filter or cat converer ... and my cat do some noise somme time like rattle is that a symptom ?? (rattle)

[@massiveyeetage8340]

If you still have it just put a heat lamp on the oil pan about 45 min before cranking it in the colder months the oil is just cold

[@shatterdome_x42xlopez49]

Wow man. I just watched this and thought the same lmao. If he still has it. Its the algorithm man.

[@SolidSnake4Ever2003]

hell, it's showing this vid to me in march 2024 lmfao, who knows if they even still have it. There's an untold of amount of things the problem could have been, they said they did a tuneup already, maybe fuel filter, fuel pump, coolant temp sensor, a ground, or just the oil and fluids being cold as hell, I live all the way in the very hot humid south USA so even I'm throwing guesses LOL more of a general gmt400 not running right troubleshooting thing..... the ignition control module below the rotor could be it too or even reluctor, dirty sticking IAC as well or all these many years later I heard it's good to replace the MAP sensor since the fumes erode the sensor over many years@@shatterdome_x42xlopez49

[@TheUndertoe]

What’s the temperatures like when your starting it

[@maddoxlogging2303]

I hear there’s good fishin in kuhbeck

[@jtorres698]

Replace the GR valve I had a problem on mine like that

[@maloz_pasoz8429]

What is GR value

[@mgs19901]

Nice truck.

[@geezusmeatball1328]

oh i try of them seafoam and lucas injector cleaner

[@geezusmeatball1328]

Ty for reply

[@kamakazecam]

What is the switch under the head lights for?

[@dirtracer21d]

Cameron Thornburg cargo light

[@c956rubber]

Fuel pump

[@devinkempa4851]

fuel injector

[@tburchfield1962]

either your starter or battery cables

[@justinrowles9316]

that whine u hear is your distributor cap and rotor gone bad replace that

[@TheJaydinrusnack]

Justin Rowle

[@TheJaydinrusnack]

Really? Mine whines in through the gears and sometimes in park

[@ianbarlow4026]

That whine is actually the power steering pump from frozen fluids until it warms up if it continues after reaching operating temps it needs a new power steering pump and possibly other power steering components unless the whining stops upon a new pump

[@ianbarlow4026]

On a gmc or chevy those should be replaced once a year

[@chrisl2090]

No thats the power steering pump. I know that sound

[@geezusmeatball1328]

can someone help me plz

[@michaelmalcolm1748]

Take off the catiylic converter

[@eduardoquintero7730]

Omg he doesn't know about carbureted vehicles!

[@DeadofWinter321]

Omg, his truck isn't carbureted jack wagon!

[@chrisl2090]

@@DeadofWinter321 well its TBI....

[@crlof9283]

😂😂😂😂

[@fivesforfun]

check all grounds especially the ones on the thermostat housing bolt. unplug the est connection for the timing and see if it starts faster if so then pickup coil needs replaced also clean IAC valve and inside of throttle body with carb cleaner and q-tips. coolant temp sensor next to thermostat housing is also a culprit of hard starts and/or rough idle.

[@barrygordon1173]

Ground on thermostat housing is wrong location...should be to intake bolt...aluminum doesnt ground

[@grettagrids]

cool accent.. are you french canadian? I have a few freinds that are.

[@geezusmeatball1328]

grettagrids yes i am lol

[@fdsjr2001able]

sometimes normal or something in the engine is hitting something these 1988 - 1998 because these type of pickup and tahoe are old i had a 1988 pickup long flat bed lots of problems first issue parking at work second issue steering breaking last issue engine nose

[@robertborum5051]

look at owners manual I had 98 Chevy 8 cylinder small block but the book said that it would have trouble starting or will not start temperatures 27°F. and below I still drove the truck through the winter but summer comes around and the issue would come back around

[@whiteline99]

Its normal for the oil pressure to drop as the oil heats up and thins out, the rought start could be vacuum leaks spray vacuum lines with alcohol based brake cleaner if it revs you found your leak just be careful and don't spray with a hot motor and don't spray exhaust manifold

[@geezusmeatball1328]

K i will try thanks for the reply but last year i changed the intake gaskets maybe its a vaccuume cause the truck die when i push the egr

[@whiteline99]

If that don't work try checking egr, let truck warm up and squeeze the egr open at idle if it drops its working if not replace also spray intake gasket with brake cleaner could be intake leak

[@geezusmeatball1328]

I allready change it and nothing change still rumble at start

[@kauto5105]

Pop pop pop pop pop pop