Question about GMC Cars & Trucks

1 Answer

What would cause a van to run rough under throttle but won't trigger a service engine light

1993 GMC G2500 5.7 TBI

Posted by on


1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • GMC Master
  • 14,585 Answers

Lots. Clogged air or fuel filter, low fuel pressure,tune up,dirty throttle body, Idle air control motor dirty, or timing out a bit.

Posted on Dec 17, 2016


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi there,
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this issue over the phone in a minute or two.

Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.

Here's a link to this great service

Good luck!

Posted on Jan 02, 2017


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Suburban 1993 2500 -454 / It runs rough on start up and then leans out and then the motor idles faster. It ran fine up until yesterday when my wife could not start it. Could it be a O2 sensor or fuel...

By "throttle body carb" I am assuming you to mean that the engine is equipped with Throttle Body Injection (TBI). The O2 sensors on that engine do not even start working for about 5 minutes. They are not going to cause a problem on start-up. A fuel filter will most likely not cause a problem on start-up or idle either. A fuel filter is most likely to cause problems on acceleration or when pulling a hill. A more likely cause would be a n Engine Coolant Temperature (ECT) sensor. If one of these is reading too low, it will cause the engine to flood and smoke black out the exhaust - especially on start-up. (LIke a choke sticking on an old carbureted engine.) If your truck is equipped with a gauge, there may be 2 Coolant sensors. One for the gauge and one for the computer. If you replace it, make sure you are replacing the sensor for the computer.

Feb 27, 2011 | 1991 Chevrolet K2500

2 Answers

I have a 1988 5.7 gmc that after start up idles fine runs stromg under full throttle but at highway speed and under no load speed it sputters and at slow speed it is running rich i have done complete...

I have a 1988 5.7 gmc that after start up idles fine runs strong under full throttle but at highway speed and under no load speed it sputters and at slow speed it is running rich i have done complete tune up rebuilt the tbi One concern i have is someone removed stock air cleaner system and the one they installed has no intake air sensor could this be the problem ?
IT CERTAINLY CAN BE THE PROBLEM. The air flow sensor if a VITAL part of your fuel delivery and emmision's system. Your mixture is controlled by a computer that uses the sensor data from that device. If you possibly can get the old one, put it back on. It is possible that I may not be totally right about this point but the operation of your engine is dependent on all the parts being there.
and also i have no codes and no ck engine light on.
There may not be code for a missing part. That system is not perfect.
I hope this helps,
Happy New Year,

Jan 03, 2011 | 1988 GMC C1500

1 Answer

93 gmc sierra running rich no computer codes

Oxygen sensor[s],map sensor and fuel pressure regulator.Although you should have a check engine light "on" with any sensor malfunction.I would look at fuel lines for a leak under vehicle.

Apr 17, 2010 | 1993 GMC Sierra

1 Answer

4.3 TBi code Z cuts out at idle. Please Help!!

Try cleaning the IAC VALVE in the opening in the throttle body with throttle body cleaner,clean well or replace IAC VALVE ( idle air control ) .

Mar 27, 2010 | 1992 GMC Jimmy

1 Answer

Runs rough. Plugs, wires, cap, rotor, timing all accounted for. Fuel filter replaced but not stopped up. No trouble codes. So, assuming all sensors working properly. Fuel leaks over the top of the one...

Two problems. First fix the leaking injector o'ring. And when you have the tbi off doing that check to see if the gasket under the tbi is blown out causing the high idle.

Aug 12, 2009 | GMC Jimmy Cars & Trucks

4 Answers

Runs extremly rough at idle runs great at speed


Jun 24, 2009 | 1994 GMC Sierra

1 Answer

Runs rough and engine light comes on

coil packs are very common on that car.
if 2 cylinders are misfire ,one pack is bad.
get a tune up,change the fuel filter and clean the throttle body,put an additive in the fuel to clean the injectors,.
if there is problems,get a scan doneto see what code is triggering the engine light.

May 28, 2009 | 1993 Oldsmobile Cutlass Ciera

1 Answer

1993 chevrolet apv van

Check the idle sensor . Have your van scanned at autozone. they do it for free.I hope this info works for you.

Nov 03, 2008 | 2001 GMC Jimmy

2 Answers

1997 GMC Savana - Car "stutters" when on incline or warmed up

their are a multitude of reasons the majority or the usual suspects are - if any codes have read and most auto stores offer this service for free --needs tune up ---egr valve carboned or failing --fuel pump /filter failing or partial clogging --catylic converter failing or clogging --injectors- tbi needs replacement or rebuild-- bad fuel any of these can cause such problems and not set off the check engine light

Apr 16, 2017 | 2004 GMC Savana

Not finding what you are looking for?
Cars & Trucks Logo

Related Topics:

16 people viewed this question

Ask a Question

Usually answered in minutes!

Top GMC Experts


Level 3 Expert

80339 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22326 Answers

Ronny Bennett Sr.
Ronny Bennett Sr.

Level 3 Expert

6927 Answers

Are you a GMC Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides