GMC

GMC troubleshooting questions? Ask a mechanic for answers

Ask an Expert,
Get an Answer ASAP!

I have a 2007 GMC Yukon Denali with low oil pressure at an…

Customer Question
I have a 2007 GMC...
I have a 2007 GMC Yukon Denali with low oil pressure at an idle. We just put in a new oil pump and pressure still drops to zero on idle. Truck runs perfect driving with Rpms up but when slowing down or stopping at idle, drops to zero buzzer comes on and engine begins to tick. Press foot on gas and start driving again- engine noise goes away and engine sounds and runs like.
Submitted: 3 years ago.Category: GMC
Show More
Show Less
Ask Your Own GMC Question
Answered in 16 minutes by:
5/21/2015
GMC Mechanic: Gary, ASE Certified Technician replied 3 years ago
Gary
Gary, ASE Certified Technician
Category: GMC
Satisfied Customers: 17,915
Experience: GCM master tech over 25 years
Verified
Welcome! My name is ***** ***** I will do my best to assist you with this problem.
is this a 4X4 ? a 5.3 engine ?
Ask Your Own GMC Question
Customer reply replied 3 years ago
AWD 2007 Yukon Denali XL 6.2
GMC Mechanic: Gary, ASE Certified Technician replied 3 years ago
did replacing the oil pump make it any better or worse ?
Ask Your Own GMC Question
Customer reply replied 3 years ago
A little worse. Before I changed it, on idle it would hold just above the red line which I thought was dangerously low. And occasionally it would drop to red which let me know I needed to do something. It dropped to red with the buzzer coming on about 4 times but not consistently as it is doing now.
GMC Mechanic: Gary, ASE Certified Technician replied 3 years ago
Thank you for that information
since the oil pump made no difference in the oil pressure and it will tick when it reads low or no oil pressure this engine internally would actually have low or no oil pressure when it acts up v/s no ticking and the oil pressure showing low but actually it has good oil pressure and just the oil sensor would be bad
at this point the issue will be a bottom end main or rod bearing issue with one or a few of the bearings that have opened up spec which will cause this issue especially after it warms up at idle
the next step to take is to remove the oil pan and plastic gauge all the bearings and see if any are out of spec if any are and the crank shaft surface is good then replacing the bearings would correct this issue
Ask Your Own GMC Question
Customer reply replied 3 years ago
The mechanic wants to change the oil pressure gauge. What are your thoughts on that. Does the oil send unit just read pressure or does it actually control pressure? Is this a waste of time and money based upon the facts of what I explained?
GMC Mechanic: Gary, ASE Certified Technician replied 3 years ago
the oil sensor just reads the pressure
since its ticking and reading low the odds are the oil pressure is in fact low
if there was no noises at all then an oil sensor would usually correct this kind of issue of the sensor bad and reading the oil pressure wrong
the oil pressure is regulated by the oil pump itself and the faster the pump spins the more pressure it makes
Ask Your Own GMC Question
Customer reply replied 3 years ago
As for the bearing job, would you recommend just swapping the engine
Or do you think changing the bearings would be easier? Never had bearings changed before. Have no clue how comprehensive or expensive that could be or the level of expertise needed to do so.
GMC Mechanic: Gary, ASE Certified Technician replied 3 years ago
if you love this truck and plan on keeping it for a long time it may be best to change the engine as it will be worth the warranty that comes with the new or rebuilt engine you buy
but if the cranks shaft is not damaged it would be a bit cheaper to fix this engine
but it really comes down to what kind of warranty you want on the engine so to say as fixing this engine will have a 12 month 12K warranty and most new or rebuilt engines come with a 5 year 50K warranty
Ask Your Own GMC Question
Customer reply replied 3 years ago
Another tech mentioned something about a pickup tube o ring could possibly cause this issue. What are your thoughts on that?
GMC Mechanic: Gary, ASE Certified Technician replied 3 years ago
the o-ring would have been changed when the oil pump was replaced and the pick up screen would have been removed also and cleaned and since the oil pan was off we are assuming the inside of the oil pan was cleaned since it was off
Ask Your Own GMC Question
Was this answer helpful?
Ask Gary Your Own Question
Gary
Gary
Gary, ASE Certified Technician
Category: GMC
Satisfied Customers: 17,915
17,915 Satisfied Customers
Experience: GCM master tech over 25 years

Gary is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.

RobinElkton, Maryland

He answered my question promptly and gave me accurate, detailed information. If all of your experts are half as good, you have a great thing going here.

DianeDallas, TX

< Previous | Next >

Meet the Experts:

Gm Tech (Cam)

Gm Tech (Cam)

GMC Mechanic

1,696 satisfied customers

GM Grand Master Technician 2007. 14 year experience.

Gary

Gary

ASE Certified Technician

17,915 satisfied customers

GCM master tech over 25 years

Dave Nova

Dave Nova

GMC Technician

929 satisfied customers

ASE Master Certification. GM World Class Certification

Chris (aka-Moose)

Chris (aka-Moose)

GMC Technician

583 satisfied customers

16 years of experience

Ron Z.

Ron Z.

- GMC Tech -

259 satisfied customers

18+yrs experience. State Inspector & GMC Diagnostics/Repair

George H.

George H.

ASE MasterTechnician

227 satisfied customers

15+ Years ASE Master Technician with Level 1 Certification

Don - Mo Lurch

Don - Mo Lurch

ASE Certified Technician

218 satisfied customers

GM, GMC, Chevrolet Cert., Heavy Line Mech, Race Shop Owner, Mobile Electronics

< Previous | Next >

Related GMC Questions
GMC Acadia SLE: my car cranks but wont start
my car cranks but wont start… read more
Gm Tech (Cam)
Gm Tech (Cam)
GMC Mechanic
Vocational, Technical or Trade Scho
1,696 satisfied customers
GM Yukon: My 2001 Yukon has no heat up front but has heat in
My 2001 Yukon has no heat up front but has heat in the back and both heater hoses are warm. I replaced my heater blower motor last winter. The air blows out the various vents. I don't seem to hear the… read more
Pete
Pete
Independent Auto Technician
Vocational, Technical or Trade Scho
138 satisfied customers
GMC Yukon XL 1500 Not getting fuel to engine on GMC Yukon
Not getting fuel to engine on GMC Yukon… read more
heavy_chevy_396
heavy_chevy_396
Vocational, Technical or Trade Scho
2,518 satisfied customers
I am working on an 03 gmc 3500 van with 6.0 v8. Engine
I am working on an 03 gmc 3500 van with 6.0 v8. Engine starts and runs fine and sometimes goes all day but most of the time after 10 or 15 min it will go to skipping and the fuel trim numbers on bank … read more
Pete
Pete
Independent Auto Technician
Vocational, Technical or Trade Scho
138 satisfied customers
Service engine soon light goes off and stays off for 3 days,
service engine soon light goes off and stays off for 3 days … read more
fordguy4u
fordguy4u
Automotive Tech
Vocational, Technical or Trade Scho
70 satisfied customers
Flashing check engine light, misfiring. 2014 GMC Sierra.
Flashing check engine light, misfiring. 2014 GMC Sierra. Just purchased this month. Husband is pretty bummed at the moment. … read more
David Craig
David Craig
OWNER/MECHANIC
Associates
5,304 satisfied customers
When I turn on the key the engine warning light comes on and
When I turn on the key the engine warning light comes on and stays on . … read more
John
John
Associate Degree
521 satisfied customers
On a 2009 GMC Acadia with a 3.6 engine which cylinders are
On a 2009 GMC Acadia with a 3.6 engine which cylinders are which numbers like 1 through 6 are 1 and 3 and 5 on the front or back head… read more
Ron Z.
Ron Z.
- GMC Tech -
Vocational, Technical or Trade Scho
259 satisfied customers
Tryng to locate engine temp gauge sending unit for 96 gmc
tryng to locate engine temp gauge sending unit for 96 gmc 2500 santa fe … read more
fordguy4u
fordguy4u
Automotive Tech
Vocational, Technical or Trade Scho
70 satisfied customers
I would like the installation procedure for an engine oil
I would like the installation procedure for an engine oil pump 2017 6.2L gmc Denail crewcab… read more
Todd Audette
Todd Audette
Automotive Technician
Vocational, Technical or Trade School
362 satisfied customers
My envoy is losing power check engine light is on and
my envoy is losing power check engine light is on and catilyic cinverter might be bad … read more
fordguy4u
fordguy4u
Automotive Tech
Vocational, Technical or Trade Scho
70 satisfied customers
Check engine light is on. Message: engine reduced power
check engine light is on. Message : engine reduced power loss, gmc Yukon denali 2007 … read more
Ron Z.
Ron Z.
- GMC Tech -
Vocational, Technical or Trade Scho
259 satisfied customers
GM yukon Denali: heated seat is not working.
Hi, my driver side heated seat is not working. When you pressed the button the light comes on for about 5-10 sec and it shuts off. The fuse labeled ignition/heated seats is fine, I replaced the heatin… read more
supermechanic
supermechanic
Service consultant
Vocational, Technical or Trade Scho
10 satisfied customers
GMC tahoe: what is the min fuel pressure on a 99 chev tahoe
what is the min fuel pressure on a 99 chev tahoe 5.7 vortec ? At idle i have 52 psi / at cruise i have 60 psi. if it is to low how do you know if the problem is the pump or the regulator?… read more
Dave Nova
Dave Nova
GMC Technician
Associate Degree
929 satisfied customers
2011 lml duramax glow plugs wont cycle enough to cold start
2011 lml duramax glow plugs wont cycle long enough to cold start the truck. Truck has new plugs and module. They module cycles for 10 - 15 seconds but glow plugs don't light just get warm for 2 second… read more
Gm Tech (Cam)
Gm Tech (Cam)
GMC Mechanic
Vocational, Technical or Trade Scho
1,696 satisfied customers
2011 gmc 2500 hd w duramax diesel. codes p0101 p205B p0381.
2011 gmc 2500 hd w duramax diesel. codes p0101 p205B p0381. all sym codes are 00. need to diagnose.… read more
Pete
Pete
Independent Auto Technician
Vocational, Technical or Trade Scho
138 satisfied customers
GMC Sierra 1500: Yesterday I got the Check Engine Light (2011
Yesterday I got the Check Engine Light (2011 Sierra 5.3L, ~60k miles) When I took it to Advanced Auto right down the street the code is P0454 Evaporative Emmssion Pressure Sensor Switch Intermittent. … read more
Dave Nova
Dave Nova
GMC Technician
Associate Degree
929 satisfied customers
on my chevy with 5.3 i put on a new oil pump and replaced the
on my chevy with 5.3 i put on a new oil pump and replaced the oil pan only the timing cover is not on ,i did put oil in the pump first to try and prime it i dont think it took,how can i prime it with … read more
Gm Tech (Cam)
Gm Tech (Cam)
GMC Mechanic
Vocational, Technical or Trade Scho
1,696 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x