I have a 98 ranger 2.5L and am having a problem with the engine stalling out while I'm accelerating. I ran the truck for 4 months with no problems at all, I parked it for 6 weeks and when I started it back up, it was a little rough at idle, when I take it out on the road, the engine goes completely dead, as if I turned the motor off, as I'm trying to accleerate. It happens in all gears (manual tranny). The truck does kick start itself after a 2 to 3 second pause while I'm rolling. I found one bad vaccuum line, replaced it but it had no effect on the problem. I also checked all other vaccuum lines and found no leaks. I started to trouble shoot other components reccomended by the service manual, but so far I've found nothing. The truck does idle good for a while, but then drops to a lower idle and stalls out. Any help would be appreciated as I do NOT want to bring the truck into a service center, sorry don't trust them!


RR98

 

Unfortunately it could be a number of things, but the one thing that comes to my mind is the fuel pump. Am I correct in assumming that your truck is FI?? If your pump is just beginning to fail, the pressure could be to low to provide acceleration, but eventually will fail to even start or idle. Do you have a friend with a fuel pressure gage?? Remember, fuel injection pressure is higher. The gage must be intended for fuel injection. Start there and see what you get. Let us know.
;-)

 

I'll check it out, thanks for the insite, let you know how it goes.

RR98

 

[updated:LAST EDITED ON 15-Oct-02 AT 05:04 PM (EST)]If you have old gas in it, that could be the problem. I hope its that simple for you.

It also could be the fuel filter. Have you changed it every 30K?

 

I just bought the truck a few months ago, it has 70K miles on it, but I'm guessing the fuel filter was never changed. I'm off to buy a new one today and try that first. I took it on the road last night and I also noticed it wasn't idling very good after it warmed up a bit. The idle kind of dropped off till the engine stalled. I'm also going to try a new tank of gas, the gas is a couple of months old in it now. If all that fails, I'm going to have to locate a fuel pressure gauge (possibly borrow one from my local parts store)and check fuel pressure. The more I think about it, I think it may be the fuel pump. I'm keeping my fingers crossed it's the filter and gas, that would make my week! Thanks again for the info, it's appreciated.

RR98

 

Have the fuel injectors cleaned. They be plugged up

 

Check the exhaust pipe for a rats nest, wasps, etc. You have a textbook example of the banana up the tail pipe trick.

 

Never thought of that, I'll check it out. Just an update, I changed the fuel filter last night since it was the easiest thing to do, but that wasn't it. I'm going to replace the fuel pump in a couple of days, I'll let you guys know what happens. Thanks again for all the help.
RR98

 

Well guys, Heres an update to my truck problems. I finally installed the new fuel pump and filter. Didn't do it. It's still not running right. I do have some more information on what's actually going on. During acceleration, the engine isn't stalling out as I originally thought, but it feel like it's being goverened. In other words, it feels like I let off the gas peddle while I'm accelerating (mostly in 2nd-4th gear). If I keep the peddle stationary, the truck will coast till the RPM's drop to around 1000RPM. Then it kicks in and begins to accelerate hard like I punched the peddle to the floor. If I let off the peddle and get back on it again, it runs normally. I drove it to the gas station and kept continually pumping the peddle, and it worked pretty good. I tested out the Throttle Position Sensor, but it's working perfectly. I'm afraid it's going to be more electronic in nature. I re-checked all the vaccuum lines and everything looks fine. I'm going to try to get the error codes read and see what they say. The check engine light did come on so something must be in there for codes. Any other things to test or try out would be greatly appreciated. I also checked the tail pipe and intake, everything looks great. I'll keep all informed as the days go by.
RR98

 

Well, I had a similar problem out of another Ford truck I used to have, and the check engine light was also on. After testing and testing, it turned out to be the throttle position sensor. I'm not arguing your mechanical ability...but are you SURE that your TPS is working properly? Electronic components do funny things sometimes.

The only drawback is, since the TPS is an electronic part, once you buy a new one you're stuck with it probably. So you'll want to be certain that you want a new one before you purchase it.

Otherwise, don't know what could cause your issue. Did you check your ignition system? Plugs, wires, etc.... Doesn't really sound like that's it though...sounds like a computer issue or a bad throttle sensor to me.

 

I actually bought the TPS and was contemplating weither or not to just pop it in. If I do I cannot bring it back. It's a $50 gamble. I was looking closely at the old one and the output from it nice and smooth, no jumpy readings. It's possible it may be erratic when the engine is running at a higher RPM due to vibrations. I'll double check everything again in a day or two. I'll run the engine this time and monitor the output of the TPS. I'm really missing the truck, my car is on it's last leg! I still have the new TPS, if I find any problems with the old one, I'll give it a shot. I think the next step is to read the codes or let the garage handle it. Of course that is a last resort for me!

Thanks for the input, appreciate it.
RR98

 

 

Well I finally got the truck running. Turns out it was a bad Mass Airflow Sensor. After replacing it, the truck is running great. Thanks to all for the help.

RR98