99 cherokee sport with difficult engine start

[99greencherokee]

I am new to this forum but I have owned my Cherokee sport for 7 years now (140,000miles).
If my vehicle sits for more than 30mins. the engine turns over several times before starting. It takes longer to turn over, depending on how long the vehicle sat. Pumping the gas expedites engine startup, but the improvement is minor. After engine start up there are no other engine problems. This problem has been continuing for 4 weeks now and I am concerned that I may wear out my starter. On another note, for a long time now my engine hesitates only at initial acceleration after the vehicle sits overnight (this problem may be related). I feel that this is a fuel delivery issue, because I added Valvoline Max Life complete fuel system cleaner to the gas tank and it fixed this issue for 2 days.

Note: I have 6yr. battery and its on yr 5. I plan to get this checked soon.

Any help would be greatly appreciated!

[dave92cherokee]

When you say that pumping the gas seems to help it get started quicker a few things come to mind. Have you ever changed the fuel filter if not then it's probably getting pretty gunked up, possible fuel pump starting to go out, TPS sensor going out, another instance of the cps crapping out as we've all seen so many of them on here. I'd start with the fuel filter first if it has never or has been a long time since being changed as it might be clogged up causing low fuel pressure. You can search on here for tps and cps and find alot of info on how to check them to see if they're starting to go out.

[99greencherokee]

Thank you for the info. Dave!

The fuel filter was my first thought, however the 99 cherokee does not have a fuel filter, it has a fuel tank module w/ integated fuel filter inside the tank. This filter is not seviceable. So the only way to change it is to buy a whole new fuel tank, which would set me back probably 500 bucks!

So, I will definate use your suggestion to check the CPS and TPS sensors. I will first have to find the threads on this forum to find out how.

Thanks again!

[wwwildman]

Originally Posted by 99greencherokee

Thank you for the info. Dave!

The fuel filter was my first thought, however the 99 cherokee does not have a fuel filter, it has a fuel tank module w/ integated fuel filter inside the tank. This filter is not seviceable. So the only way to change it is to buy a whole new fuel tank, which would set me back probably 500 bucks!

So, I will definate use your suggestion to check the CPS and TPS sensors. I will first have to find the threads on this forum to find out how.

Thanks again!

First Welcome to the forum.

Second, you are correct that the fuel filter is inside the tank and is part the module, but it is actually an integrated, fuel filter/fuel pump, which is replaceable.

I would first do a fuel pressure check to make sure that the fuel pressure is within range or not. If out of range I would suspect the fuel filter/pump or other fuel line restriction.

You may also be able to take the Jeep to a parts store and see if it has any codes. If it does then you will be able to start there.

Mike

[sswpriz]

I had the same problem with my 99 cherokee, turned out it was the fuel pump !!! They had to drop the tank to replace it !!!

[wwwildman]

Originally Posted by sswpriz

I had the same problem with my 99 cherokee, turned out it was the fuel pump !!! They had to drop the tank to replace it !!!

Yes, but it is not that hard to do yourself. The hardest part is lowering the tank (get as much gas out as you can), and disconnecting the rubber hoses that go to fuel filler door where the gas cap goes.

[Rich_cad]

If it starts no problem when it's cold but won't start without pumping the gas when the engine is hot, it is most likely the engine temperature sensor. Check the wire going to the sensor, pull the end off, clean it really good, and plug it back in. This fixed my 97 cherokee. It's quite possible the sensor has gone bad, but I bet the connector is just dirty.
The link below goes to a write up on testing the sensor.

Hope this all helps.
Rich

http://www.autozone.com/servlet/UiBr...3d801523cb.jsp

***cut and pasted below***
The engine coolant temperature sensor, or ECT sensor is mounted by the thermostat and provides the PCM with engine temperature information. The PCM supplies 5 volts to the ECT sensor circuit. The sensor is a thermistor which changes internal resistance as temperature changes. When the sensor is cold (internal resistance high), the PCM monitors a high signal voltage which it interprets as a cold engine. As the sensor warms (internal resistance low), the PCM monitors a low signal voltage which it interprets as warm engine.

[m48shooter]

wwwwildman, my fuel pump/filter just crapped out... planning on remove replce in the am... can u run me though the process... thx