2005 Montana SV6 3.5 LITRE starting problem

  • Thread starter Thread starter skruffy
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skruffy

I have a 2005 Montana SV6 with a 3.5 litre engine that starts normally when it is cold without putting my foot on the accelerator pedal but once it warms up and I have to restart, I must press down on the gas pedal otherwise it kinda starts then shuts down or runs for a brief second at 500 R.P.M. or so. Again, when its warm all I need to do is give it gas by pushing down on the gas pedal but my wife is complaining more and more!!!! Please help guys, I cant find anything even though Ive done a lot of searching and reading.:mad:
 
Does the engine service light come on?
It could be a few things:
The IAC (idle air control) is dirty or not working properly.
The fuel pressure could be bad (dirty fuel filter, weak fuel pump, or bad fuel pressure regulator)
Dirty or bad injector.
Bad engine temp sensor. (Could be telling computer it's still cold and thus giving more fuel when it doesn't need it)

Since it starts normally when cold but not hot, I would start with the fuel area first. Having to hold the gas pedal down a little suggests the engine is not getting the correct amount of air/fuel. With fuel injected cars you should never have to touch the gas pedal when starting unless the engine gets flooded with fuel.
 
Thanks for the reply!! The check engine light does not come on. I will now continue with your suggestions by starting with some injector cleaner and the I.A.C. you mentioned. I did a major tune up last year and replaced all plugs, wire set, air filter, etc. but it still did the exact same thing after this was done? I did notice that there is NO FUEL FILTER THAT CAN BE REPLACED ON THIS MODEL. On another note, one more thing I notice upon mild acceleration is a faint whine at a certain R.P.M. similar to a vac hose being off but have not been able to find one off???? This could also be the main reason for this........Ill have to find a vacuum hose schematic and follow it through also.... Any more ideas? Thanks again!!!!
 
Thanks for the reply!! The check engine light does not come on. One thing I forgot to mention is at a certain R.P.M. ,I hear a faint whistle/whine from the engine area similar to a vac hose.......I am going to find a vac hose schematic and look into this further. As for your suggestions, I am going to look at what you suggested, I recall when I did the major tune up that there was no fuel filter listed??? Im probably going to begin with some injector cleaner and continue on with your suggestions. Any other ideas? Thanks again for your reply!!!
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Wasnt finished yet but it posted on me accidentally.... anyway, ya, I hear this slight whistle type noise and was going to begin whit finding a shematic of the vacuum lines, then continue on with your suggestions. I realize if a vac line was off or had a cut in it, it could be this but after I satart it, it idles fine with no rough idle or anything??? Thanks again Orief for the reply, I really appreciate your input!!!
 
No service engine light, the van idle speed stays steady when a/c, headlights, heater etc is on. The engine temp. gauge on dash is normal. After reading further in the Haynes manual, Im leaning toward possibly the Engine coolant temp. sensor???? If it is malfunctioning, it would assume that there would be additional fuel and less oxygen entering the cylinders???? Like I said, when its cold the engine starts perfectly and once it warms up, I need to depress the gas pedal for it to start. Other than this, it runs perfectly!
 
To verify a bad coolant temp sensor, drive it until it warms up then stop at an Auto Zone or NAPA auto parts store and have them read the PCM engine temp. If it still shows the engine is "cold", The sensor is bad.
 
Montana 05 SV6

I got that similar problem. Look like start better when it cold then hot. The check engine doesnt appear but i got impossible to star in the Message box. (even tho sometime the engine is running) Where can i find that temps sensors? is that something i can do ?
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Like oreif said in the post before , have someone pull the codes from the van's computer and that would be a starting point.
 
Steelcity said:
Like oreif said in the post before , have someone pull the codes from the van's computer and that would be a starting point.
Click to expand...

I will do that it just i dont think NAPA do that here in québec so i have to pay like 50 buck just to get the reading that piss me off.
 
No Autozone in Quebec?
 
melsg5 said:
No Autozone in Quebec?
Click to expand...

nope and i just made some call and yea i cant find a shot who just read it for you. I think im gonna just buy a code reader since i got to read my other car also.
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I had the same problem with my 05 sv6 and i found out the throttle body was all dirty had a build up of sludge i used throttle body cleaner cleaned it and changed the air filter now it idles and runs fine now hope this helps
 
http://www.youtube.com/watch?v=LwOV2F0ZCek This Video by Westonnesbit (I do not own it) Is the same thing im experiencing right now or since i had the van. Again it only happens when warm otherwise theres no problem at all. Tell me what you guys think about it, a friend said it might be an electronic problem.
 
http://www.youtube.com/watch?v=LwOV2F0ZCek This is a video by Westonnesbit (I do not own this) This is exactly what is happening to me right now or since i got the van. It only happens when the engine is warm otherwise it is fine. A friends says it might be and electronic problem.
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did you do a fuel pressure test? did you check the fuel pressure regulator? did you have someone with a scanner check if the ECM is getting the correct temperature reading?
 
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