Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN









Search Auto Parts

Transmission Help


  Email This Post



debruck
New User

Dec 18, 2011, 1:24 PM

Post #1 of 11 (2003 views)
Transmission Help Sign In

I need some help with a 2001 GMC sierra 1500. When the engine is cold there is little to no power when pressing on the accelerator. It will idle along slowly but when you go to pull out into traffic there is no power. I am not sure if this could be fuel pump malfunctioning or if it is transmission problems. When it does this is makes a pop sound like it is missing on a cylinder or something like that. I recently put on new plugs and wires so I dont think it is missing. After you idle for a little while it works fine. When in neutral or park the engine will rev up like normal but when in gear it does not until it warms up a little. I had a guy test the fuel pressure and he thinks it is the fuel pump, I question if this is the case because when in neutral or park it doesnt seem to have trouble like it does when in gear???

There is 155000 miles on the truck and I have not had problems with it until now?

Any help would be appreciated. Thanks


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 18, 2011, 1:47 PM

Post #2 of 11 (1974 views)
Re: Transmission Help Sign In

What was the fuel pressure when he tested it?



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Discretesignals
Ultimate Carjunky / Moderator
Discretesignals profile image

Dec 18, 2011, 1:51 PM

Post #3 of 11 (1970 views)
Re: Transmission Help Sign In


Quote
I question if this is the case because when in neutral or park it doesnt seem to have trouble like it does when in gear???


That is because more fuel will have to be injected if the engine is under load and the vehicle is accelerating. There isn't much of a load in park or neutral while your reving the engine.

Best thing to do is watch O2 voltages to see if they are leaning out under load.





Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.


debruck
New User

Dec 18, 2011, 2:42 PM

Post #4 of 11 (1960 views)
Re: Transmission Help Sign In

20 PSI and I was told it should be about 40.


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 18, 2011, 2:47 PM

Post #5 of 11 (1951 views)
Re: Transmission Help Sign In

Hell no. That truck needs a minimum of 55PSI to run even though you never gave us yhe engine size. None are any lower. You need to check that again because it shouldn't run at all if those pressures are correct.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



debruck
New User

Dec 18, 2011, 3:00 PM

Post #6 of 11 (1945 views)
Re: Transmission Help Sign In

It is a 5.7L 4X4 Z71.


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 18, 2011, 3:04 PM

Post #7 of 11 (1938 views)
Re: Transmission Help Sign In

You sure about that? I don't see that even being an option in '01

What are the 8th and 10th digits of the VIN#?



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



(This post was edited by Hammer Time on Dec 18, 2011, 3:09 PM)


debruck
New User

Dec 18, 2011, 3:31 PM

Post #8 of 11 (1929 views)
Re: Transmission Help Sign In

You are right .. it is a 5.3L

So would you say that I should start with the fuel pump?

I think that is what it is. My fuel gauge is shorting out lately and will report accuratley for a while and then it will fall to empty then back to normal. I have been going by milage for fuel level and when the fuel goes down from full and the guage reports as normal it is pretty accurate, but it will short out and report empty a majority of the time.


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 18, 2011, 3:35 PM

Post #9 of 11 (1922 views)
Re: Transmission Help Sign In

Only blame the pump after you have verified full power and ground arriving at it but bad pumps are real common. So are fuel gauge problems. Make sure you get a complete fuel pump assembly with the gauge sender. Delco brand is the better way to go.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.



Sidom
Veteran / Moderator
Sidom profile image

Dec 18, 2011, 4:25 PM

Post #10 of 11 (1916 views)
Re: Transmission Help Sign In

I'm surprised it would even start.....


Hammer Time
Ultimate Carjunky / Moderator
Hammer Time profile image

Dec 18, 2011, 4:27 PM

Post #11 of 11 (1910 views)
Re: Transmission Help Sign In

Yeah, that's why I want him to check it again. That doesn't add up.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.







  Email This Post
 
 


Feed Button




Search for (options) Privacy Sitemap