GMC Yukon Start Stall Idle Problems

qness

I love my 2001 Yukon xl Denali with over 130,000 miles but having some starting problems. The initial problem was taking several tries to start, when after it seemed a clog was cleared and the engine banged loudly once it would clear and start and be ok for the rest of the day, but a little more difficult in colder weather. I brought it to a small gas station where they kept the vehicle over night, recognized the problem but couldn't diagnose. I went to the dealer and they couldn't even find the problem after keeping it over night.

The problem is now getting worse. I have to keep pumping the gas rigorously several times and restart several times to finally get it to turn over and actually start--it is not weather dependent and a little harder to start even after the vehicle has been in use during the day. It has never not started, but I really don't want to get stuck somewhere.

I don't know what to do or where to take it---any advice.

tbensor

Here is a wierd one for you all. Once this truck gets below a 1\4 tank it will not start sometimes. The other day it did this with 3\8's of a tank. Basically you can run it all the way down to empty and as long as you put fuel in it, all is good. If you shut it off under a 1\4 tank, leave it over night it won't start. If you put a gallon of fuel in it, it will crank. This happend the other day and there were still 10 gallons of fuel in it when I filled it up, so I know it is not a guage issue. Maybe the pressure regulator?

yukonjake

listen to see if the pump is turning on. if you have a fuel pressure gauge, hook that up. should be around 50lbs +/-3

jcanbounc

After my 93 yukon has warmed up and I shut it down. When I go to restart it, it will not start. It will turn over and act like it want's to start. I pull the number 1 plug and see if I am getting spark I get a real weak spark and then nothing. If I let the vehicle sit for a little it will fire right up. I have replaced (coil, icm, rotor, cap.) The wires and spark plugs are good. I thought it might be running a little hot, so I replaced water pump, therm, as well as the temp sending unit. When I do the code reader I get 54 and 32. Having a lot of trouble figuring this out. I have been working on this for about 3 week's any help would be appreciated

popo111

I am now having idling problems when the vehicle approaches red lights or comes to any stop. It starts right up without problems. It has 102,500 miles on it and has been great until now. If anyone has any suggestions that might shorten my visit to the repair shop tomorrow, it would be greatly appreciated. Thanks in advance.

stormnn

Did you change the spark module under the rotor? My 93 did the same thing.

popo111

I have not. I will be bringing it in this morning and maybe that info will help. I appreciate it. I will post the problem and resolution when it is completed. Thank you.

popo111

OK....I took the Denali to the shop and they fixed it. It actually stalled once on the way there and tried twice at stop signs. It turned out to be 'the throttle body was sticking'. They cleaned it and $150.00 later, It is working again. Thanks again fro your help and maybe this info will help someone else.

slywuf

I need some in depth technical help please - here's the long sad story in 3 part harmony: Recently this Yukon (5.7L Auto Trans) would start fine in the morning, drive fine to work, start up fine after work, but shutting it off 1/2 hour later and trying to restart again would get no action from the starter at all. Let it sit and hour and then it started up fine. Happened again the next day only this time it took 2-3 hours before it would restart. I thought the starter was the culprit, so spent big bucks on a new starter and put it in.
It started up just fine but the next time it was driven for a while and shut
off for about 30 minutes, it would not restart again... not even after waiting
more than 12 hours. Here are the results of some testing that I have done:

No check engine lite was ever present, and plugging in my OBD2 reader showed no error codes. Security light seems to function normally - stays on for about 5 seconds after turning on the key and then goes off.
The fuel pump does run when the key is turned on.
The fuses are good.
The starter relay is good. Jumped across the output terminals of the starter relay socket and the starter cranks fine, motor starts but will run for just a couple of seconds.
The ignition switch on this vehicle was just replaced about a year ago.
According to the factory manual that I have, there is supposed to be a ground present on one side of the starter relay (coil side) this is pin 85 on the relay, and then when the ignition key is turned to start, there should be +12 volts on the other side of that relay coil which is pin 86. I dont see either when I put my meter on there. The diagnostics dont appear to take into account the theft deterrent system, which I suspect may be the reason. Should I be able to see theft deterrent trouble codes with the OBD2 reader as well? I tried adding a ground to pin 85 of the starter relay but it still wont start. What else can I do to figure out what is keeping the starter relay from working? Is there a way to bypass the theft deterrent system? HELP ! I'm stuck.
Thanks in advance.

chennigan

ive been driving my denali for about a year ,no probs,yesterday i went to go to work and the dash went crazy weird crazy and starter just clicks sometimes,sometimes nothing not even dash lights i think it might be the ignition switch because if i play with the key sometimes the dash works normal till i touch the key again to try to start it and it goess half dim and freakn out gauges...HELP

jmuncan

I have a 1999 GMC Yukon that will not start. The battery is not dead, but the engine will not crank over. I have voltage up to the fuel pump relay. I think it may be an electrical problem. Does anyone have any idea what is going on? It is now going on 3 days.......

yetirider

Last summer my 02 yukon XL died while my wife was driving, she said it would lose power, and die, it restarted a couple of time, drive for a few miles, the same thing. we replaced the fuel filter, and got it home, test fuel pressure, all seemed okay. My daughter drove it for a week, on a trip, and it did it one time when she got back to town, stalled, restarted, got home, and no problem since, until yesterday, did the same thing, power lose, then dies, happened about 6 times, but she got home.
Any ideas?

rsht

Possibly moisture in the system...

heazzz

I have a 2003 and I found the crankshaft positioning sensor was bad it is behind the starter on the passenger side - drop the starter and you can get to it thru the wheel well -Good luck

djtwisted

I have a similar issue with my vechicle not starting. Through research i have found out that when i replaced the fuel pump my vechicle started right up with no issues. For some reason GM fuel pumps only last about 100,000 miles. This has fixed one of my many problems i hope this helps you.

jmorehouse

120k mi hard to start, rough idle, fouled plugs. Dealer says bad injectors. I replaced all injectors, no change. Cold start good. I just don't know what to do next. Plugs, wires, injectors, fuel filter, air filter all changed. Help?

rsht

Have you checked the vacuum lines for any possible leak?

emart1

have you had any luck ...I'm having the same problem with 99 GMC yucon ( emart401@msn.com) I kind of think its in the security system...

fongerelli

Your idle problem could be a clog throttle body and /or IAC (Idle Air Control)valve. If you have a Vortex motor (V-8), this might likely be the problem especially if you have not had your IAC changed out or your throttle body cleaned. Let me know if this works for you.

fongerelli

I looked at the arm of the sensor on the body and where it touches the frame, and I'm looking at the shaft (plastic with no adjustment to it) but yet the manual saids that it is adjustable? What can I do without altering it like mounting a bracket on it to go higher? Anyone know or know of anyone doing this with their autoride?

Help!

john8009

My 1992 yukon wont start unless you add gas straight to the carbuertor. It will run fine after that but as soon as you turn it off you can't start it unless you readd gas to the carburetor.

rcortez

Hi Yetirider,
I just purchased a 2009 gmc yukon a few days ago. On the second day my wife was driving it and while attemping a slow left turn the vehicle died and she then pulled to the side of the road and it started right up. She was driving it today and it did the same thing. I drove and it did have some hesistation to it. I called the dealer and asked the service advisor if he had heard of this happening and he said know. I will take it in this week for a diagnostic. It sure doesn't look promising since I am already having problems. A vehicle that dies on you while driving is very dangerous. Will let you know what they find.

fongerelli

I never had that problem and I had my yukon for 9 years now. If it continues, under the lemon law you qualify to receive another vehicle at no extra charge. My expertise would have to say there is something going on in the brians of the operation so have them hook up the computer to the Yukon and see what it says. It could be lots of things i.e. fuel injection, electrical , or computer telling everyone else to shut down because of something you know? I hope this helps and I know its frustrating especially when you just spend lots of money supporting an icon like GM and this happens.

coach17

I have had the same experience with my 02 yukon xl (108,000 miles). Recently on two(400 mile) trips the truck stuttered and stalled while driving. After sitting for a few moments the truck started and ran fine. After the the first occurence, I replaced the wires, spark plugs, and fuel filter. A week later the same thing happened. Any ideas???

fongerelli

I have an 2000 Yukon (with the new body style) and I have 102,000 miles on it. I have never experience that yet, But I had the similar situation with my Jag, It would stall at an idle, and it started up after I tried but you had to baby the gas pedal to get it going again. You might want to check out the mass air meter (expensive 300-500) or go to a junkyard, because once I replaced that in the Jag it was normal again. Back to the Yukon, I have never had to change the Mass Air Meter in it yet but i did put a chip in it to get better gas mileage or so they say. I have a feeling that GM installed a sensor device that once you reach a certain mileage it starts to stall and etc.. Once you know how to reset that portion you should be fine. If you hooked up a computer to the Yukon system it should indicate the issue that you have, I hope? Look at all of your filters too and make sure the system is running without any obstacles in it's path.

rcortez

I have the yukon at the dealers right now. I will let you know what they fine. funny thata 2009 yukon is doing the same thing wtih only 40 miles on it at the time. It has done it twice so far.

coach17

Di you ever find out what was wrong. My 2002 yukon xl does the same thing.

fongerelli

check your mass air sensor or your control valve sensor or have your throttle body cleaned. Let me know.

chicks100

Yukon dies while driving, no sputtering, no stalling, just dies. Runs fine after restarting. Any suggestions to the problem???

fongerelli

I have had my Yukon going on 9 years now and I have not experience that yet. But I did experience it with my other car and it was the mass air sensor, It is that unit in front of the square air cleaner unit. You might want to be very careful when cleaning it with carbertor cleaner and re-install it and see what happens and if not that You need to take it in and have a meter connected to it so it can identify the problem. I hope helps you?

rcortez

I have a 2009 yukon that has died 3 times while slowing to a stop. Took it to the dealer and they could not find any problems, after I drove off with it died 3 miles down the road. This has been 3 weeks ago and has not done it since. The milege is bad only getting 15 miles to the gallon in the city and the highway was supposed to get 15 city 20 highway. I do like the vehicle but worried about the longevity. Through this forum have heard of this similar problem through out the years before. I will try to have the dealer ship sign off on a promisary note to fix vehicle even after the warranty has ran out ifthis problem ever returns, if they don't agree will write a letter to gm.

04denalixl

I have a 04 denali XL with a little over 76,000 miles and surprisingly this is the first problem I ever had with it. Last week, my wife was driving it and came home. I got in it and went to pick my kid up from the bus stop and was on a decline and little did I know, it was low on gas. When I restarted the vehicle, it sounded as though it was flooded. but after 3 tries, it started and I took it home. After getting home, I started and shut it off, repeating the process several times to see if it was just me or the truck. After letting it sit overnight, I woke the next morning and tried to start it and it again sounded like it was flooded. But it always starts on the third try. I haven't taken it to the dealership and really don't want to because I know that if I do, the police might have to drag me outta there with the BS that they try to give out so any suggestions would be great. Thanks in advance. :sick:

fongerelli

Were you assuming that it sounded like it was flooded? When you say flooded, did you smell gas? or did the engine just kept cranking over and over and no hope of catching a spark? You might want to check the gas filter? since you were on a decline and on very low gas (this is where all of the junk from the inside of the gas tank and fuel goes through the system and gets the fuel filter plugged with crap). Secondly, if that doesn't work check your mass air control unit. But since this is a newer vehicle, if you can borrow the tool that plugs into the computer of the car it will indicate to you (by code) what the issue is with your Denali. I hope this helps and let me know the status...

zzxxyy2

2004 Yukon Denali XL, engine 6.0L, all wheel drive. On around 09/01/09 my parents started to feel that their vehicle was stumbling, hesitating, or stalling on at acceleration. This vehicle would start and idle with no problems, but at hard acceleration the vehicle would hesitate really bad and generate a code P0336. I searched the code and it was for P0336 “Crankshaft Position Sensor A Circuit Range/Performance”. Bought a new crankshaft position sensor from an autoparts and installed it. With the new sensor the vehicle would just crank and not start. Soon it would generate a code and it was P0335 “Crankshaft Position Sensor A Circuit Malfunction”. Removed the crankshaft position sensor and returned it to the autoparts, they gave me another one to install. It also did the same and generated the P0335 code. Removed it and returned it to the autoparts and they gave me another one which it also gave me the P0335 code. After the third crankshaft position sensor, the autoparts gave me my money back. I went to the dealer and got me a new one, which are made from ACDelco for $87.03. Installed it, the vehicle started right away, took it for a test drive and all the stumbling, hesitation, and stalling were gone.
Note: The crankshaft position sensor is located in the passenger side of the vehicle. It is between the starter and motor.

04denalixl

I guess I was assuming that it was flooded but did not smell gas. She still cranks on the 3rd try and I hear my fuel pump kick in everythime I turn the key. I had her on the highway yesterday at high speeds and everytime I punched it, she took off with the power that she always had. She never stalls or shuts off and I see that she is gettting fuel, but on the way back, my service light came on and I took it by the parts store to read the codes, and they said that the connector wasn't getting power so they couldn't read the codes. But this morning I went to the store and it was on when I got there. Switched the truck off and went inside and came out 5 minutes later and did the 3 try start thingy and the light was off. I'm thinking that it may be a computer problem or something as well. I did just recently get a new battery installed. Wondering if you have to reset the computer when installing a new battery? But I will also replace that crankshaft position sensor and see what happens. Thanks for the responses as well everyone.

retfire

just got back from dealer,again.brought all my info on the recall and told him that i read about others having same problem.he told me,again,that the trucks computer needs to pick up the problem so they can fix it,and that he can't remember a recall.this is what we are dealing with.he stated that they reprogrammed something to do with the sluggishness the car was having.again,nothing found that would address the problem of my truck stalling.and i can't turn the truck in like i posted earlier.it is a new program and you may return the vehicle if not satisfied if you purchased it between sept.15 and oct.15.i purchased my truck in late july.am calling gm today,i will post what they said.

conleyge

Hello to all, I have a 2002 Denali, which had the engine (a used 6.0) replaced after the original took in water. The replaced engine is also a 6.0 but a 2005 and not a 2002. Since the replacement of the engine, the Denali's service engine light has been on, and runs rough (with the service engine light blinking) after you have gave it gas and the vehicle has been at high rpms to pass a vehicle. Recently, the fuel pump and crank sensore were replaced and the codes were cleared, which I thought had corrected the problem. The vehicle ran great with no service engine light for about three days and then suddenly started the same nonsense. Can anyone help? Thanks in advance.

lbathke

My Denali just started idling funny. When sitting at an idle, it will every once in awhile act like its going to die then go back to idle again. It also does this when driving it when I come to a stop. I tried it out last night and every time while sitting in park I give it gas then let off it acts like its going to die then goes back to idle again. Any ideas?

fongerelli

Sounds like you have a dirty IAC (Idle Air Control Valve) which is the silver unit just before the throttle body on the top of front of engine. that could possibly be dirty or dirty fuel lines, dirty injectors. What is the idle at when it is normal, i.e. around 600 rpm or lower? And when you say its getting ready to die, look at the idle needle on the tachometer and if it falls below 400 or under it will die. If you know anyone that has a scanner or a diagnostic tool, it will tell you the code and I can look it up for you. Also, in the old days before fuel injection, we use to have carburetor with air fuel mixture screws and idle screw so that we can adjust the idle to where we want it, but in yours the IAC controls the idle and the PCM ( Powertrain Control Module) controls the IAC. Let me know what happens.

mikelong

Our Yukon will crank but not start Ive replace the fuel pump and fuel psi reg and still the same thing help

lbathke

So I have replaced the air filter, spark plugs, and fuel filter. I also had the alternator and battery checked for s&g's. Still have the same problem. The vehicle idles around 500 rpm or a little lower. I have not been able to locate the IAC. I have added some of that fuel injector cleaner additive to my tank to see if that helps. When it acts like its going to die it hits about 300 rpm according to my tachometer. I will check that next. It is supposedly on the air intake next to the alternator. Any other ideas if the IAC doesn't pan out.

coach17

I cleaned both the mass air sensor and the throttle body. It appears to have addressed the problems I was having. There are spray cleaners for both of these items. Just be careful and follow the instructions on the cans.

fongerelli

The IAC is attached on the front before throttle body unit EFI (electric fuel injection) its small aluminum color and has plug to it and it is at the end of the plastic air intake unit where the hose clamp is located. Be careful in handling this unit and spray a special cleaning spray (get from auto parts store) the IAC and re-install it and see if the idle goes back up to 600 rpm. when cold the idles should be around 1,000 or so and after it warms up in gear around 550-650 rpm. If you have the heater or a/c on it affects the idle too so make sure they are turned off. Do some research on the IAC (Google it) or go to u tube and type in "how to clean my IAC unit properly"
I hope this helps.....

mamom

I own a 2007 Yukon with approx 40K miles. Twice in the past three months the check engine light has flashed on for about two seconds and when that happened the engine derated and then all is fine. The other day on a trip the engine light flashed on and did the same thing. About 20 minutes later it did it again but this time the messages that flashed are stabilitrack disabled, engine power reduced and then the car shut down on the highway going 70+ miles and hour. The car then would not start. My husband wiggled some wires and the car started. We got to our destination and then home no problem. We took it to a mechanic to check the codes before bringing it to the dealer. NO codes showed up on the computer. Any thoughts on what this could be? I drive this car with my children all the time and do not feel safe.

rsht

Per you description, it does sound like some sort of bad connection. Can you describe what wires did your husband wiggled and if the wires lead to the engine in-take area?

mamom

Not sure on exact wires but I believe they did go to the engine intake area. he also changed the relay??? Had our mechanic look it over and he said all wires looked ok-nothing obvious and b/c no codes were detected there's really nowhere to start. Spoke to the GM dealer local to us and basically said the same thing and wait til it happens again-not very comforting. Seems odd that a vehicle can completely shut down and the computer doesn't pick up any codes.

surfnaked

Important. If you have to replace a your 02' IACV, GMC will make you buy the WHOLE Throttle Body Assembly @ a cost of $850 bucks. They will not sell you the IACV individually, and you can not buy it new from any WEB SIGHT parts house. The ones they claim FIT, ARE THE WRONG APPLICATION!

FYI!

surfnaked

Clean throttle Body!!!! U may need to replace the Throttle position sensor or Idle air ( manually clean it out. 80% of your problems will begin in the Throttle Body!!

FYI............GMC will not sell U a Idle Air. They make you by the Whole $850 TB assembly. Dont attempt to buy from Online auto parts house! They will not fit!!!!
Model's referenced 2000-2002.

mrkuhls

I HAVE A BRAKE AND ABS INDICATOR THAT COMES ON INTERMITTENTLY. WHAT COULD CAUSE THIS?

fongerelli

so how many miles do you have on the suv? did you check the brake fluid level? Or it could be a loose wire to the computer? I need more information that this?

mrkuhls

I HAVE 80,000. YES ALL FLUIDS ARE TOPPED OFF. PADS CHANGED, FRONT AND BACK AT 75,000.