Engine Mechanical problem
2000 Ford Ranger 4 cyl Two Wheel Drive Manual 15000 miles
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My low mileage 2000 Ranger won't start on hot days (>90 degrees F). Sometimes, I will start it in the morning, drive it with no problems, park it and then come back out 2 -3 hours later and it won't start. Sometimes I try and start it mid-day and it won't start, and sometimes I start it mid-day and it starts (all days are in the 90s). Ford Dealer said it could be the fuel pump, but of course it started fine when I had it towed to the dealer, so the mechanic didn't really know if it was the fuel pump. Mechanic said it might be electrical and said to tap the relays if it happened again. When it happened again, I tapped the relays - no help. I assumed they checked the fuel filter, but not sure (since when it runs, it runs fine, it doesn't seem to be a filter problem)

When I say it won't start, it turns over fine, starter engages and turns the engine over quite normally, just won't start. I have tired turning it over for upto 15 secs - still won't start.

With such low mileage it doesn't seem like it should be the fuel pump, plus once it is started it runs fine.

This is something that needs to be troubleshot when it's happening. I've seen pcms do strange things like this. If it isn't starting, try removing the pcm and throw it in the fridge for 15-20 minutes and then plug it back in.

IF the pump is suspect alone, a shor of carb cleaner into the throttlebody will act as replacement fuel for a few minutes.

Both fuel and spark should be checked when this is happening.

This is something that needs to be troubleshot when it's happening. I've seen pcms do strange things like this. If it isn't starting, try removing the pcm and throw it in the fridge for 15-20 minutes and then plug it back in.

IF the pump is suspect alone, a shor of carb cleaner into the throttlebody will act as replacement fuel for a few minutes.

Both fuel and spark should be checked when this is happening.

Sorry - but what is pcms - where would I find it. Thanks

Powertrain Control Module. AKA computer. I believe it is on the right hand side of the engine compartment around the firewall area.

Should disconnect the negative cable first before removing it....if you are comfortable doing this.

Powertrain Control Module. AKA computer. I believe it is on the right hand side of the engine compartment around the firewall area.

Should disconnect the negative cable first before removing it....if you are comfortable doing this.

I think I have located the PCM and it's relay. I'll give them a shot of compressed air (try and cool them down) next time I have a problem. The PCM is pretty big, so the compressed air may not cool it down a bunch, but it is worth a shot. Beyond that it is back to the dealer. One last question, wouldn't the computer capture some type of error code if the PCM was at fault. Thanks again.

IT may or it may not. I always like to check the codes regardless, as a clue may pop up to aid....or completely throw you off track, lol. Since this problem isn't consistant completly with the hot weather, it may be a false assumption.

IF a pcm is not right, it can do different things that aren't right.

Now that you mention it, a plastic bag of ice cubes with a cloth wrapped around it would do a the cooling thing. Sometimes we use this method as a final confirmation after running through the trouble tree charts or if it is intermittant in nature.

IF there are two relays the same, you can try swapping them and watch for a failure of the other circuit.

IF all else fails and this remains intermittant, when you take it in to the shop, ask them if the service manager is willing to drive it as a personal car until the problem happens. I work in an independent shop and we frequently do this for customers in the intermittant situations. Saves the customer diagnosis money and the Boss gas money.

Pull the oil dipstick, and check for a higher level than normal, oil being thin or the presence of fuel. This may tip off to this being loss of spark as oppossed to fuel.

I'm having this very same problem right now with my 2003 Ford Ranger. The dealer is convinced that it's the fuel pump but I don't think so, since the problem is directly connected to the outside air temperature, usually over 82 degrees or so. I had the same problem last summer but no problems at all until we hit 80 again this summer. It will start just fine in the morning or when it's been off for a while, but if I'm driving around and I turn it off, if I come back 10 or 15 minutes later it might start but immediately stall. However, in 30-90 minutes of cooling off, it starts just fine. I can tell it's not going to start because the fuel pump doesn't engage. I had it to a local mechanic and I was able to duplicate the problem, and he also didn't think it was the fuel pump, although we could hear both the fuel pump relay and another relay I think he called the "fuel injector pump relay" engaging, but the fuel pump didn't start. He referred me back to the dealer, he just had a small shop. Occasionally, it seems if I hit the gas pedal at just the right moment during cranking, it will start, but again, that could just be at the right time the temperature has cooled. It's almost 90 here today and I've gotten in touch with a somewhat compassionate service manager at a small dealership where I live, so I'm going to see if I can get it there and duplicate it at their shop. I'll post my results, but I'll also try the icepack on the PCM.

I haven't had the problem repeat - but I haven't been driving the truck much because of the problem. I should have some time this week to further test the "cooling down" method.

Jbecker - I'd be interested (obviously) in what your dealer tells you. Thanks for participating in this string.