2.9 ranger runs terrible

[preston c]

I have a 2.9 5 speed ranger. I have made a prior post to this but didn't fix the truck.I stopped fooling with the truck for a while but I'm coming back to it. The truck has a low idle and will die after running for a while. When you give it throttle it misses really bad. Most of the time after giving it throttle it dies too.It had codes for IAT and ECT sensor out of range so I replaced both. This fixed my IAT code but it still says my ECT is out of range. I had to replace ECT connector too.I got the truck to the running temperature and it still says its out of range. I done a fuel pressure test on it and it stays around 40 psi which is what it calls for. I've checked for vacuum leaks, pulled off iac and cleaned it, replaced the fuel filter and probably more I can't think of. One more thing , the fuel pressure relay clicks rapidly after the truck runs for a little bit (I don't know if this is normal or not). I have no idea what else to check.

Any help would be greatly appreciated.

 

[franklin2]

Clicking rapidly is not normal. Sounds like you have a wiring connection problem somewhere. You will have to go over the complete engine harness and see if you can find something.

 

[preston c]

Clicking rapidly is not normal. Sounds like you have a wiring connection problem somewhere. You will have to go over the complete engine harness and see if you can find something.

okay thank you, I will check more on it tomorrow.Also forget to mention i fuel pressure tested it when it was clicking and it didn’t drop my pressure at all. Do you have any idea what the clicking would cause?

 

[franklin2]

Are you sure it is the fuel relay clicking? There are several relays over there. I think there is a main EEC power relay, the fuel pump relay, and a WOT relay for the A/C clutch.

 

[preston c]

Yes, it’s the green relay from what i’ve read and test i’ve done it’s the fuel pump.

 

[rusty ol ranger]

Yes, it’s the green relay from what i’ve read and test i’ve done it’s the fuel pump.

I believe the ECM sends power to the fuel pump relay. If its clicking rapidly i would bet its a wiring issue or an ECM issue.

That could be whats going on with the coolant sensor too. I believe there is a way to use an ohm meter to measure the sensor and see if its reading properly...but im not sure on how....google might tell you.

You can remove the ECM and open the case on it (fairly simple process) and look for obvious issues...but thats not a 100% gurantee its still good.

 

[preston c]

Okay, Ive tried to chase the fuel pump wiring and coolant temp wiring and I cant find any obvious issues. I will try the ecm thing also. I went to start the truck the other day to mess with it and all it does is back fire a lot and die. I'm wondering if the distributor could be out of timing too, but I don't have any special tools to re time it.

I'm so lost on this thing I have no clue what else to check and I'm not the best with electrical.

 

[Shran]

Backfires through the exhaust or through the intake?

Lots of things can cause that - timing issues, damaged valve(s), lean condition, fuel leaking into intake or exhaust, ignition module problems, etc.

Easy way to check timing is to pull your #1 spark plug, rotate the engine by hand until it is at top dead center on the compression stroke (you will feel air pushing out) and then rotate the engine so that the crankshaft balancer markings have "0" or TDC or TC or whatever it says aligned with the timing pointer. Then pull your distributor cap off and see which plug wire the rotor is pointing at. Should be fairly close to #1, and #1 is usually labeled on the cap itself. If it's way off, you can turn the distributor so that it points right at #1 and then borrow a timing light to get it timed correctly... but if it was stabbed wrong in the first place, you may not be able to turn it far enough and will need to pull it and stab it correctly so that #1 is about in the middle of its range of motion.

Not sure what to say about the clicking relay. That sounds like a bad relay or faulty wiring... flaky ground maybe or something corroded. IIRC those relays are all the same, you can swap them around and see if the problem follows the relay.

 

[rusty ol ranger]

Okay, Ive tried to chase the fuel pump wiring and coolant temp wiring and I cant find any obvious issues. I will try the ecm thing also. I went to start the truck the other day to mess with it and all it does is back fire a lot and die. I'm wondering if the distributor could be out of timing too, but I don't have any special tools to re time it.

I'm so lost on this thing I have no clue what else to check and I'm not the best with electrical.

One other thing....have you tried pulling the codes?

 

[preston c]

One other thing....have you tried pulling the codes?

yes I have code 51, (ECT out of range)

 

[preston c]

Backfires through the exhaust or through the intake?

Lots of things can cause that - timing issues, damaged valve(s), lean condition, fuel leaking into intake or exhaust, ignition module problems, etc.

Easy way to check timing is to pull your #1 spark plug, rotate the engine by hand until it is at top dead center on the compression stroke (you will feel air pushing out) and then rotate the engine so that the crankshaft balancer markings have "0" or TDC or TC or whatever it says aligned with the timing pointer. Then pull your distributor cap off and see which plug wire the rotor is pointing at. Should be fairly close to #1, and #1 is usually labeled on the cap itself. If it's way off, you can turn the distributor so that it points right at #1 and then borrow a timing light to get it timed correctly... but if it was stabbed wrong in the first place, you may not be able to turn it far enough and will need to pull it and stab it correctly so that #1 is about in the middle of its range of motion.

Not sure what to say about the clicking relay. That sounds like a bad relay or faulty wiring... flaky ground maybe or something corroded. IIRC those relays are all the same, you can swap them around and see if the problem follows the relay.

It backfires through the exhaust. What could I check within the ingtion module, how would I check leaky fuel?

 

[rusty ol ranger]

yes I have code 51, (ECT out of range)

Start with that. Check the wireing, change the sensor....

Exhaust backfire is generally caused by av overly rich condition...which ECT issues can cause.

There is a way to check the ignition module...but im not sure how...i believe its pretty complicated and kind of a worthless test since TFI's generally shit out when warm.

Best way to check for injector leaks is to put a pressure tester on the rail and see how fast the pressure drops

 

[preston c]

I've already changed the ECT sensor. I've tried checking the wiring and didn't see any thing but I'll look again.and I've checked how fast the pressure dropped too, and it tested okay.

also does anyone know where all of the grounds are located?

 

[preston c]

Backfires through the exhaust or through the intake?

Lots of things can cause that - timing issues, damaged valve(s), lean condition, fuel leaking into intake or exhaust, ignition module problems, etc.

Easy way to check timing is to pull your #1 spark plug, rotate the engine by hand until it is at top dead center on the compression stroke (you will feel air pushing out) and then rotate the engine so that the crankshaft balancer markings have "0" or TDC or TC or whatever it says aligned with the timing pointer. Then pull your distributor cap off and see which plug wire the rotor is pointing at. Should be fairly close to #1, and #1 is usually labeled on the cap itself. If it's way off, you can turn the distributor so that it points right at #1 and then borrow a timing light to get it timed correctly... but if it was stabbed wrong in the first place, you may not be able to turn it far enough and will need to pull it and stab it correctly so that #1 is about in the middle of its range of motion.

Not sure what to say about the clicking relay. That sounds like a bad relay or faulty wiring... flaky ground maybe or something corroded. IIRC those relays are all the same, you can swap them around and see if the problem follows the relay.

also i forgot to mention i switched the relays out and when i connected the other relay to fuel pump harness it wont even click. they seem to be the same relay too

 

[Shran]

Well that's not ideal... does it run with the relays swapped? I have had plenty of those go bad, usually they get wet and everything inside gets corroded. There is a cap that you can pop off to look at the insides...it's basically the whole top of the relay. It might not hurt to hit up a junkyard and grab a few spares for testing.

Have you tested the fuel pressure with an actual gauge? You should be seeing about 35psi at idle and up to about 40psi if you blip the throttle. Anything much different than that will cause issues, especially low pressure. Lean conditions from low fuel pressure will cause backfires...usually through the intake. Your fuel pressure should hold steady when you shut the engine off, it should not drop much if at all over days if not weeks or months. If it drops on its own, that is a problem, it's either leaking past the injectors, at the regulator and into the vacuum lines, externally, or backwards through the pump.

Should be two small black wires that go under the battery tray and up to the negative battery terminal. Those commonly corrode off and get hacked back into place with wire nuts or clamps or other junk... those two wires are your ECM and fuel pump ground, the truck will not run or not run well if those are not connected and in good condition. I can't tell you how many of those I've fixed on hopelessly broken trucks... a small issue that causes big problems.