Question about Cars & Trucks

1 Answer

1989 f-250 starting issues

When the truck has sat for a while (overnight), I start the truck and the RPMs will fluctuate a second and then the engine will turn off. I will have to turn the engine over for about 10 to 20 seconds, sometimes longer and the engine will finally turn over, all the while blowing smoke out the pipe. The truck runs fine when started. It seems like the discrepancy will gradually get worse the longer it will sit before being started (a couple hours after sitting and attempt to start the truck, the RPMs will fluctuate but the engine will still continue to run. leave the truck sit overnight and then start the engine is when this issue is the most annoying. I suspect it might be a pressure regulator, but I cannot find it. Is it internal to the injector pump?

Posted by on


1 Answer

  • Level 1:

    An expert who has achieved level 1.


    An expert that got 5 achievements.


    A rookie expert who has answered 20 questions on their first day.


    An expert who has answered 20 questions.

  • Contributor
  • 20 Answers

Is it diesel and what color is the smoke (white or black)?

Posted on Nov 04, 2012

  • scott bries Nov 05, 2012

    it is a diesel and will spew white smoke while trying to restart



6 Suggested Answers

  • 2 Answers

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

a 6ya expert can help you resolve that 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.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

  • 2 Answers

SOURCE: 1999 suburban starting problem

It is possibly a PASSLOCK problem. Before you start the vehicle, place ignition in RUN and observe the "SECURITY" light. Under normal conditions, it should go out after about 5 seconds. Once the PASSLOCK is activated, the vehicle wil not start for 10 minutes. If you have access to a OBD-II code reader, you will see a code stating a problem with the security feature, code P1626. The problem is most likely a intermittant failure of the contact in the ingnition switch responsible for this signal.

Posted on Jan 06, 2009

  • 95 Answers

SOURCE: 1985 diesel after sitting overnight will not start

The check valve is a small brass fitting where the return line attaches to the filter head. I believe it takes a 7/16" wrench. There is a 'duck bill' inside that prevents fuel from leaking back to the tank causing air in the system. It should allow flow in only on direction. Some times you can see light through it if it's bad enough. Also, the lines between the injectors can dry out and start to leak air. Air will leak in before fuel leaks out, and you won't see it. There are plastic, cup-shaped connectors for these hoses that press onto the top of each injector. They are sealed by two o-rings on each injector body where it meets the connector. These o-rings can dry out and also leak air and fuel. Your Ford dealer or diesel service professional should have the proper o-rings. Any other o-rings might not seal, as they won't be the exact size. You already changed the fuel solenoid when you replaced the pump. It is inside. There has to be battery cranking voltage to it while cranking, and battery voltage with key in 'on' position. The wire attaches to the top of the pump. This is not likely to be the problem, since it restarts every 2 hours.

Posted on Jan 11, 2009

  • 1 Answer

SOURCE: hard starting after sitting awhile

I posted the second problem, I did get my car fixed. the problem was a weak fuel pump

Posted on Jan 19, 2009

  • 59 Answers

SOURCE: turns over but won't start

I'm guessing this vehicle is a diesel. From your description, it sounds like you may have a fuel system problem, bad fuel injector, bad fuel pressure regulator, or possibly even a problem with the fuel injection pump. The white smoke you spoke of is unburned fuel and you are right the system is flooded and takes a little bit of running to clear out. I would highly reccommend taking your truck to a repair shop. The longer you delay, the more likely that you'll cause additional damage to other systems, for example the starting system and charging system as well as shortening the life of your batteries.

Posted on Aug 27, 2009

  • 500 Answers

SOURCE: 2004 mustang fuel pump issue, start car runs for a

sounds like the fuel pump is getting tired

Posted on Sep 11, 2011

Add Your Answer

Uploading: 0%


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



Related Questions:

2 Answers

This engine has a surge; AT 35-45mph,it's a bit more prounounced, not as bad, but still there at 60mph. As the tach goes up some, then down, so does the motor, up then back down, etc.Any ideas?

About 73,200 results (0.82 seconds) Search Results

    Surging While Driving Between 40 and 50 MPH : Chrysler ... > Problems > Chrysler > Town & Country
    Around 35 mph (common street speeds) the engine will sometimes surge with noticeable tach fluctuations. ... I have a surge when coasting around 40-45 mph.

    Enginge surges RPMS drop while driving [Archive] - Chevy ... > ... > OEM Issues

    Mar 17, 2012 - 19 posts - ‎7 authors
    [Archive] Enginge surges RPMS drop while driving OEM Issues. ... I so hope somebody has a clue as to what is causing my '02 Envoy's (182k) engine to ... I'll be driving and when I get up to around 35 - 45 MPH sometimes my ...

    Hesitation and bucking on acceleration - F150online Forums

Feb 09, 2016 | Cars & Trucks

1 Answer

I have a 2001 Chevrolet Impala LS 3.8 and it starts and idles fine in park but while driving the rpms aren't where they normally are and fluctuate a lot sometime causing the car to surge or jerk.

Possible ignition misfire causing this problem. Is the check engine light on/flashing? If so, have the codes scanned to help, isolate the problem. Even without the check engine light on, the computer will sometimes store a code that can be helpful in diagnosing this issue

Oct 18, 2015 | Chevrolet Cars & Trucks

1 Answer

Pontiac 3400 misfire problem one new coil pack new plugs and wires on still running bad have too press gas too start now bad fuel mileage unburnt fuel smoke when engine starts for a few seconds then stops...

some of the cylinder wont get spark, faulty spark plug, wire or coil. To check pull all spark plugs out, plug them to the wires and put on the engine top and then cranck the engine to see which spark plug not giving a spark

Apr 16, 2014 | Cars & Trucks

1 Answer

RPM revs high and changes while in neutral

Check the air intake sensors, called MAF or MASS air flow. They have temp and baro devices in them.

Feb 05, 2014 | 2007 Toyota Corolla S

1 Answer

3.0L ford engine misfired now check engine light stays on.

You can take it to an Auotzone, Advance, or Oreilys parts store for a free scan. They can then reset the computer and tell you what the old defect was.

Please rate my info.

Dec 04, 2012 | Cars & Trucks

1 Answer

I have a 1998 GMC Sierra, 5.7 liter Vortec 4x4. It has 160k miles. I have noticed that it idles at around 500 rpms when its warmed up. Not sure if this is normal. However, I have noticed a bit more...

The normal idle for your engine should be 550 to 600 RPMS so thats not to far off . But the fluctuation is more likely the crank pisition sensor then the EGR valve this engine has a condution called crankshaft wip witch is normal but going down a rough road can somethimes set off a misfire code It wouldn't be a bad idea to take the EGR valve off and clean it and check it but the CPK would give you the fluctuation in RPMS . It still could be a few outer things but this it the most likely cause

Apr 02, 2011 | 1998 GMC Sierra

1 Answer

My 2005 Colorado RPM's fluctuate on a cold start up, from normal down to 500 Rpm. The truck starts fine, but as soon as I have to push the clutch in and stop, the Rpms will fluctuate about 3x and then it...

eddyblueange_2.jpgthis is an idle valve after 1996 the ecu control the idleing from the engine with this air by pass if this valve is geting bad it can get stuck open or closed or dont working right is an electric selenoid ......... listen for air leaks ....... wen you push the clutch you push the brake too check the brake booster

Dec 28, 2010 | 2005 Chevrolet Colorado

1 Answer

99 jeep cherokee with 4.0 straight six takes extra long to start

The request doesn't say what the problem is...takes extra time to start?

Sounds like fuel-related - injectors/fuel pump/fuel filter? Is there a strong fuel smell or black exhaust for a few seconds/minutes after starting it when it's sat overnight? If so, then you've got a leak causing excessive fuel...kind like 'flooding' the engine on old cars w/Carbs.

It could also be the temp. sensor. If it thinks the car is 'warm' it won't give the car enought fuel to start when cold.


Jul 23, 2010 | 1999 Jeep Cherokee

1 Answer

Engine light is on and when started rpms are up and down for a few seconds

I wold suggest that you go to a auto-zone or other auto parts store an ask to borrow there diagnostics reader to read the error code activating the check engine light. At most places they will allow you borrow one free of charge and will even help you with diagnosing your problem but from what you said I would say it sounds like you crank shaft positing censer as that tell the engine when to fire and can cause your fluctuation in rpm.

Hope this helped.

Thank you.

May 16, 2010 | 2005 Ford Escape

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

Related Topics:

106 people viewed this question

Ask a Question

Usually answered in minutes!

Top Cars & Trucks Experts


Level 3 Expert

76164 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22156 Answers

Randy Ohler

Level 3 Expert

14585 Answers

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

Answer questions

Manuals & User Guides