Question about 1999 Jeep Cherokee

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Power pulse when i start the engine from cold i step on the gas, and the engine power pulses, almost as if its not getting fuel? I get no codes and already have changed fuel pumps and spark plugs. Also no drop in the fuel pressure line. If the engine is already warm from running, it does not have the problem.

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It sounds like one of your sensors (MAP or MAF)is not getting the needed vaccum when it's cold. I would recommend an upper intake flush. Most of your local shops know how to do this. It will clean the carbon out of the intake and open the vaccum ports to al the sensors.

Let me know how this works out for you....

Posted on Sep 07, 2008

Try replacing alot of the sensors, last reading i got on the computer was for the downflow O2 sensor was shorting, going to try and replace that once i get one in

Posted on Sep 07, 2008

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96 tahoe turns over but wont start 1/2 tank of gas carbs clean gas gets to carb but i got no spark I just change the distributor' coil the MAP sensor new plugs and wires last November and really haven't...


Did you visually check for spark at the spark plugs, engine cranking? Does the dist rotor turn when you crank it? Did you use a gage and check correct fuel pressure? Any applicable trouble codes? To check codes, yourself, at the least, you need an obd2 code reader.

If you have the spider fuel system, that system is noted for problems. No, the fuel system shouldn't cause a no spark. If no rpm signal, that will usually stop the injector pulse along with other issues.

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I have a 1994 chevy s-10 pick-up. I just replaced the gas tank, sending unit and fuel pump. Still won't start Prior to doing this I tried to drive it last week. It started and ran for about 2 minutes and...


Check the distributor cap and rotor.... If they look originial or if there's any moisture inside the cap, replace both of them.
Make sure that if you do replace them that theres no moisture in the distributor before putting new parts in.

Oct 21, 2013 | Cars & Trucks

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I have a 1990 chevy s 10 with a 4.3 engine it starts when cold will idle a few minutes then dies as a result of not getting fuel if I pour gas down the throttle body it will restart but only run l,ong...


Could be loosing power or pulse to the injectors. I would check for power and pulse ground at the injectors and see if you are loosing one or both.

Dec 24, 2012 | 1990 Chevrolet S 10 4WD

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Won't start when cold


Are the Injectors pulsing?

Oct 18, 2011 | 1995 Chevrolet Blazer

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1996 Concorde LXi 3.5/63k mi, won't cold start (in


it might be your fuel pump. I gotta tell you though you shouldn't start changing parts at random. it will become a money pit

Feb 19, 2010 | 1996 Chrysler Concorde

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99 Tahoe engine cranks, wont start


You need 3 things.
Compression
Good hot blue spark to all plugs.
Good gasoline and proper fuel pressure. 63-64 lbs.
If you have all 3 then move on to injector pulse to all injectors.
I think each injector is on a separate driver on that one.
Check for pulse to all of them.

You may be weak on fuel pressure . even a couple of lbs low on a cold start will cause a no start.
Double check cold start cranking fuel pressure. If under 63-62 lbs you have problems.
one test is to give it a squirt of carb cleaner not starting fluid. If it starts then you have a fuel pressure problem.
Run the full fuel pressure test and post back pressures.
Here is the guide lines on testing.
Hard to start cold.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
Later V6 and V8 gm engines should have 60-66 fuel pressure.
Cold start should be 64-65 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 60-66 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak.


The 75-85 is only a check on the capable full pressure of fuel pump.
If you can not find the rubber return line check full pressure by plugging return line or just or the true full pressure can be taken direct at the end fuel filter.
What are the pressure readings that you have done.
What are your cold start pressure readings?
Post back what you have.


The other thing to that is common is the (ICM) under the distributor cap. There is a breather screen on the bottom of the distributor that get's clogged with dirt causing condensation promoting corrosion, this was gm TSB for replacing the cap and rotor to make sure it's clean.

Good luck and hope this helps. Merry Xmas.

Dec 24, 2009 | 1998 GMC Safari

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No codes will not start Engine cracks OK. 60 lb. fuel pressure. Has spark. This problem started after I replaced the transmisson.


i would check for any LOOSE OR MISSING GROUND WIRES that were originally bolted to either the bellhousing/starter bolts or if the wiring harness that runs over the tranny and connects to tranny switches has been cut/damaged. you would be suprised how many problems can occur because of bad/ missing grounds!!

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2 Answers

2001 silverado 6.0 v8 starting problem at mid temperature.


On Saturn car it turned out to be a coolant temp. sensor so look there. simple 12 dollar sensor that screws it all up. So i would say look into a coolant temp. sensor

Feb 13, 2009 | 2001 Chevrolet Silverado 1500

1 Answer

Hard Start with trouble code 32


You should have your battery checked, it may be getting old and doesn;t have as much cold cranking power, I don;t think code 32 has anything to do with the slow cranking when cold.


Trouble Code 32 indicates that the Exhaust Gas Recirculation (EGR) valve diaphragm is not where the ECM expects it to be. The ECM controls the diaphragm with a Pulse-Width Modulated (PWM) waveform. The EGR has a vacuum bleed solenoid that adjusts the vacuum applied to the EGR valve based on this pulse width. If there is sufficient vacuum at the EGR valve, a switch closes to send a signal back to the ECM. The absence of this signal is the bases for code 32.
The conditions for setting this code are:
  • no vacuum to EGR (switch open), and
  • Code 33 or 34 (MAF error) is not present, and
  • engine running and LV8 is less than 100, and
  • coolant temperature is > 118 deg F (48 deg C), and
  • the EGR solenoid duty cycle is < 65%, and
  • the above conditions are met for more than 25 seconds


Typical causes for this code include:
1) Faulty EGR valve-to-ECM connection
2) Plugged EGR passages and/or sticking EGR valve
3) Defective EGR valve
4) Defective ECM

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