Question about 1994 GMC Suburban

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Speedomter moves while car is in park and idling witch is causing engine to run bad

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Your right about the run bad the engine and battery grounds are the reason. Under the batery and around their are many diferent wires that are connected to the bidy and the raditor suport right around the battery, After awhile they get rusted and the connections become bad. Remove the battery and the battery box and you'll see the problem, all of these cars do it some. Take every wire off and clean them with a wire brush till they look like new and the place they connect to the body, theirs more than a few so look around their are more on the firewall and in all the kick panels and in the cargo area anywhere near a light. the ones near the battery give the most problems and get them and any that look bad and any that look good do em anyway. the fire wall has grounds too but they don't fail much but engine work and engine changers get in a hurry and leave them off jump starters tend to burn some of the grounds though and bad plug wires can send power were it needs not to go the ingtion coil can get burnson the sides that are a telltale. the ingtion module itself can fail partly as the coil leaks, watch it run in the dark and you might see the problem or if your brave just run your hands over the wires and parts till you feel the problem. ( might even knock you for a loop ) Don't forget to clean the battery cable ends real good ( looks like new money ( I use a powered wire brush on a die grinder) ( get-r-done)

Posted on Sep 17, 2010

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No response on the throttle but idles ok!

you posted to USA forum with a car we dont have,
so ill attempt to answer based on rules of Mr, Otto Cycle engines.
even fails in park or neutral ,no way to race engine fast at all?
be key evidence that.... yah?
car dont move, right? in any gear, is transmission a stick or auto.
we cant guess transmission either.
so ill pretend engine power is nill.
top causes. in no order.
  1. bad fuel
  2. low fuel pressure
  3. no tune this decade, spark and filters.
  4. CEL lamp in cluster glows running and you ignoring it.
  5. scan the PCM
  6. check fuses.
  7. get car serviced.
  8. bad engine.
  9. is idle speed normal hot? engine?

Mar 28, 2016 | 2010 Suzuki Alto 1.0

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Car stalls after turn or idle

Q; Is your service engine lamp on? This vehical has a power steering pressure switch,witch helps your engine maintane idle at parking lot monuvers. its next to your power steering can check if it works by starting your engine and let it warm up. then without tuching your gas pedal turn your steering wheel slowly , the engine should maintane its idle. if this works and your service eng. soon is not on then try cleaning your throttle plate. A dirty throttle is alot of stalling causes with all vehicals.

Jan 18, 2012 | 2000 Ford Focus

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1988 toyota crissada,runs hot,idles to high.going 5 miles per hour and speedomter say 130 mile per hour,has very little power.

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Nov 08, 2011 | 1988 Toyota Cressida

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Dies out when its in park runs good

When you are in park, your getting less gas and less air. OK, if you haven't changed the fuel filter in awhile, might want to. You could have a vacuum leak on the engine. In all honesty, there are several things that can cause this. You may have a bad idle control sensor or the idle may need to be adjusted. It could be in the ignition system, a weak connection. Is your check engine light on? Does it only act up in park?

Mar 04, 2011 | 2003 Mitsubishi Galant

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My car is cut off complete when i drive, but in "P"parking is no problem, what can be?

To answer your question I must put this in two parts , Firstly if the idle is low and you shift from park to drive and the engine stalls this is due to the idle being too low. When you shift from park to drive the transmission puts extra load on the engine causing it to idle lower and thus can stall. Remedy to fix is to either screw up idle adjuster but most times it's because of built up carbon in the intake throttle body causing the accelerator flap inside to not fully close . This causes the throttle positioning switch mounted on the side of the throttle body to send the wrong signal back to the computer saying that the car is not at idling position when it is. Remedy to fix this is to spray in some Carby Clean into the throttle body and then some more while the car is running, all while holding revs up on motor so it will not stall ( use the whole can ).
Now the second part is that you can have a bad wiring problem with either a broken wire or bad connector . When you put the car into Drive from the park position the engine will rock ( this is on all front wheel drive vehicles ) If you have a broken wire or bad connector some where between the motor and cars wiring loom by the engine moving it can open circuit any connection that controls engine running . Remedy to fix is to put the car into park and physically move and jiggle wiring in engine bay until symptoms occurs , then it's up to you to repair the fault

Feb 27, 2011 | 2000 Daewoo Lanos

1 Answer

I have a 1991 Buick Park Avenue. Runs rough in

Here are the common cause of surges, cold stalls, stalls at stops, slow idle speed, erratic idle speed, rough idle and engine hesitation (and other problems), it is in most cases the idle speed control air-bypass valve and or throttle valve and upper intake, these area's get full of gunk and combustion residue over the miles and cause idle issues (stalls, low idle) like yours.
To correct this problem I want you to get a can of intake cleaner (ABOUT $5.00) from any local auto parts store like NAPA or Carquest, do not use carburetor spray, intake cleaner only or u will damage the Teflon coating inside the throttle valve and air bypass valve, it is made by a company called CRC, remove the air intake hose to the engine, hold the idle high so the engine won't stall, then spray the can of cleaner into the intake while keeping the engine running, use at least 1/2 the can, shut down the engine and disconnect the battery for 5 minutes, then restart and complete a number of mixed driving cycles, town, freeway, stop and go etc., after a few days the problem will go away as the system will relearn to the clean intake.

May 25, 2010 | 1991 Buick Park Avenue

2 Answers


this is what we call "dieseling"
it is the engine running WITHOUT spark plugs

This happens when you have leaking injectors and carbon build up in the engine (pistons/valves)

try shutting off the engine while in park
keep your foot on the brake because you might find the engine has enough power to actually move the van

keep us posted

Apr 12, 2010 | 1998 Dodge Caravan

1 Answer

1990 Ford Probe 2.2 automatic stalls in forward, reverse OK

Sounds like a bad IAC (idle air control valve/sensor) that controls your idle when going from throttle to idle. If bad your idle will act crazy and can cause stalls easily. Pretty sure that's it.

Dec 20, 2008 | 1993 Ford Probe

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