Question about 1999 Mercury Cougar

1 Answer

Car idles low, stalls after start

When starting my engine it will start up and stall or idle at a low RPM around 400-500. To start i have to put foot on the gas and keep it at about 1500 rpm and easily let off gas so it wont stall, if i just let off gas it stalls until engine is warm. 2.5L V-6 with manual 5-speed transmission.

Posted by on

  • Anonymous Mar 17, 2014

    Rund ok for a while but when car 'warms up' it starts to 'cough and splutter' when you go around a corner and put your foot down - or just put your foot down when you start off - it's ok when you get up to speed ?????

  • Anonymous Mar 17, 2014

    starts every time, have to keep foot on hte gas so it will not stall again. Once it is warmed up, it's not a proble.

×

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Top Expert:

    An expert who has finished #1 on the weekly Top 10 Fixya Experts Leaderboard.

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

  • Mercury Master
  • 61,249 Answers

Common issue at the shop (i'm a ford technician), here is what I do to correct it.
Here is the most common cause of surges and stalls at stops and low erratic idle speed and rough idle, it is the idle speed control air-bypass valve and throttle valve (IAC for short), they get full of gunk over the miles and cause idle issues (stalls, low idle) like yours, Get a can of intake cleaner from any local parts store, not carb spray, intake cleaner, 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.

Posted on Mar 11, 2009

  • jimyfmbrz763 Mar 16, 2014

    when puting all the parts I took off when replacine fuine, I noticed air breather hose having alot of gunk in it. havnt tried solution yet, but even if thats. ot

×

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

Periodically, EPS comes on Dashboard ,then steering becomes too hard, this will disappear two to three times re start the vehicle or running few meters and switch off the car and re start the car.


well I can't drive it and see all symptoms.
i can't see the idle speed drop below 800 RPM,. !
if the idle drops real low, then engine shakes, and PS gets weaker.
Id ignore the EPS till such time as all other things are perfect.
ever get an engine tuneup this decade?
low engine RPM , top number 1 cause is owners not servicing their cars. (spark plugs bad tops that list)
if you ignore that, tuneup the engine WILL misfire and RPM will drop and P/s (means power steering)will get weak (the assist is pump driven) and then the engine can stall.
i bet you also forgot to say the steering got weak
park or coming to a stop with foot off throttle.
do the head lights dim as this (bad) happens?
can you use your right foot to keep RPM above 800 and save stalls or near stalls?
IF RPM is ok, ?then check the fan belt next. (slips)
or buy a new on, my guess is 11 year old belt is kinda hopeless case.

Aug 14, 2015 | 2004 Suzuki Swift

2 Answers

2002 rodeo, starts and when put on gear stalls


Automatic transmission ??
Check engine lamp illuminated ??
Cold engine idle speed ??
Warm engine idle speed ??
IAC (Idle air control) system operation ??

May 28, 2015 | 2002 Isuzu Rodeo

1 Answer

94 jeep grand cherokee. starts,idle. throw warmup. as soon as I touch the excellerator let up the rpm drop & engine stalls.


Most low idle speed problems on these engines are due to a faulty idle air control valve but since you state the idle will go up and return to idle then i would say it is working properly i think you have a throttle body coking problem ( dirt and grit accumulates around the butterfly valve in the throttlebody ) to fix this simply remove the fresh air hose from the throttlebody and open the throttle all the way up use a clen rag and wipe clean you may use a solvent such as B12 on the rag but dont use too much 1_4_2013_4_54_06_am.jpg

Jan 04, 2013 | 1994 Jeep Grand Cherokee

1 Answer

Car will not start without pressing gas pedal to keep idle speed up. If I keep idle at 900 RPM or higher it runs as long as foot is on gas pedal. It then stalls out when I take foot off gas pedal. No...


Have the idle bypass valve checked, also called idle air control valve.
If that valve is stuck in the closed position, it's not allowing the fuel to bypass the throttle plate to keep it idling, resulting in stalling, but will keep engine running if the pedal is pushed down.

May 14, 2010 | 2000 Toyota Camry Solara

3 Answers

Engine idles to low and stalls


I would have the throttle plate cleaned because when they get dirty they have the symptoms that you are describing

Jan 24, 2009 | 2000 Volvo S40

2 Answers

Low idle, stalling frequently


Hi, Check all vacume hoses and fittings make sure there are no vacume leaks also make sure ignition timing is correct.

Dec 01, 2008 | 1987 Toyota 4Runner

1 Answer

1988 jeep cherokee idles rough, and will die while driving


Sounds like it could be a bad map sensor.
Black smoke?

Sep 16, 2008 | 1988 Jeep Cherokee

1 Answer

Truck starts and idles down as normal. If one guns it the revs will soar. If one tries to increase the rpm gradually the engine quits at about 2000 rpm. At this point if one lifts ones foot of the gas...


You may have a vacuum leak. My problem was with the L-shaped rubber hose at the top of the engine near the firewall. It had collapsed and dry-rotted. Replaced it and my truck runs like a gem. I believe it was fouling out my coils on plugs. This may not work, but would not hurt to try. Good Luck!

Aug 12, 2008 | Ford F-150 Cars & Trucks

Not finding what you are looking for?
1999 Mercury Cougar Logo

3,088 people viewed this question

Ask a Question

Usually answered in minutes!

Top Mercury Experts

yadayada
yadayada

Level 3 Expert

61249 Answers

Fordexpert

Level 3 Expert

5331 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

21949 Answers

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

Answer questions

Manuals & User Guides

Loading...