I need my injection's!

[compaqeo]

88 2.9...Guys im having troubles getting my rig running started with fuel pump then starter and now it still wont run. It has spark and is timed correctly, i sprayed some gas in the intake and it fired on that for 1-2 revs but nothing more. i did a fuel pressure check at the rail and it has 43 psi. So i then went about taking the intake manifold off to get at the injectors i tested the wires with a voltmeter while cranking and it was 0 the whole time for about 5 secs of cranking.


soo what to check, what to fix, what to do?
Cant try anything till tuesday but as many answers and ideas would help big time so i can get this thing going.

 

[fordman4488]

Had the same problem in mine when i bought it. Turned out being the computer, but could posibly be the fuel relay, or a ground not making connection. Just have to start tracing wires to make sure all have good connection and go from there.

 

[compaqeo]

Had the same problem in mine when i bought it. Turned out being the computer, but could posibly be the fuel relay, or a ground not making connection. Just have to start tracing wires to make sure all have good connection and go from there.

I wired the fuel pumps up separately so it doesn't use the relay, i have a fuse in the wiring along with the inertia switch and a toggle switch on the dash. So unless the Relay controls the injectors it couldn't be that? Reason i wired them up is it still would not get power to either pump. Is there any way to test the computer? Also about how much was your computer (new or used)?

 

[fordman4488]

Not sure if the relay controlls the injectors, but that is what i was meaning, dont have the diagram here to look. And I bought a new one at autozone with a 1 year warrenty for $130 iirc.

 

[compaqeo]

i really hope its not the computer but it probably will be. Anyone else have any in sight on this?

 

[BillupsOMally]

I had something similar happen twice. First time the computer became partially unplugged after several hundred thousand km's, and the second time the grounds in the harness right by the computer went bad.

Also, I was helping someone trouble shoot a Honda and discovered that a multimeter won't register voltage on the injector circuit. Once we got it running we tried it again and it still didn't register. That may not be the case with the 2.9 system, but thought I'd share.

 

[RyanL]

I had something similar happen twice. First time the computer became partially unplugged after several hundred thousand km's, and the second time the grounds in the harness right by the computer went bad.

Also, I was helping someone trouble shoot a Honda and discovered that a multimeter won't register voltage on the injector circuit. Once we got it running we tried it again and it still didn't register. That may not be the case with the 2.9 system, but thought I'd share.

You just beat me to it, but I was about to say that I think that the computer sends pulses to the injectors, not a steady stream of power. It would be difficult to actually test. I would be affraid of putting a test light on one of the connectors because it might draw too much power, but might be alright (maybe someone with a little more knowledge has some input). Maybe a small LED from radioshack or something would be better. I've been doing a lot of reading about 2.9L Fords recently and I thought I remember coming across an issue which keeps the injectors from firing (it may have actually been a TFI issue since that was what I was mostly reading about, but could've been something else). Anyway, see what codes you have if any. Your computer could be shot, but it might be something else.

 

[compaqeo]

You just beat me to it, but I was about to say that I think that the computer sends pulses to the injectors, not a steady stream of power. It would be difficult to actually test. I would be affraid of putting a test light on one of the connectors because it might draw too much power, but might be alright (maybe someone with a little more knowledge has some input). Maybe a small LED from radioshack or something would be better. I've been doing a lot of reading about 2.9L Fords recently and I thought I remember coming across an issue which keeps the injectors from firing (it may have actually been a TFI issue since that was what I was mostly reading about, but could've been something else). Anyway, see what codes you have if any. Your computer could be shot, but it might be something else.

Don't have a OBD-1 reader unfortunately...tomorrow im going to test the TFI and the injectors with a redneck node light i guess if both of those work im trading it for a Yota...ha ha jk but seriously i wish i got one from the start Rangers are a pain to work on, look better then Toyota's though.

also my check engine light is on 24/7 with the key out maybe thats connected with my no start issue?

 

[Earl43P]

Look at this schematic http://www.therangerstation.com/tec...es/Diagrams_ElectronciEngControls2_9_1of3.JPG
http://www.therangerstation.com/tec...es/Diagrams_ElectronciEngControls2_9_2of3.JPG
http://www.therangerstation.com/tec...es/Diagrams_ElectronciEngControls2_9_3of3.JPG

Power is always present at the injectors connectors (with the key in Run) and the PCM pulses grounds.

You may have a bad PCM relay if your CEL is on with the key Off. Might also be an ignition switch problem.

 

[RyanL]

Don't have a OBD-1 reader unfortunately...tomorrow im going to test the TFI and the injectors with a redneck node light i guess if both of those work im trading it for a Yota...ha ha jk but seriously i wish i got one from the start Rangers are a pain to work on, look better then Toyota's though.

also my check engine light is on 24/7 with the key out maybe thats connected with my no start issue?

I was going to tell you that you could get the codes without a OBD-I reader on our trucks with a little jumper wire and 3/16" blade connectors on the ends (you can get them at radioshack), but I'm not sure if it will help in your scenario if the CEL is always on. I guess it wouldn't hurt to try though. If your ignition switch was stuck on, I would think that other things would be on all the time like the radio or blower fan. It's looking more and more like a bad computer. I hate to tell you to buy one especially if it is a wiring issue, but maybe you can find one real cheap on craig's list or something (people part out rangers and bronco IIs all the time). I was able to find a few parts myself on craig's list.

 

[RyanL]

Look at this schematic http://www.therangerstation.com/tec...es/Diagrams_ElectronciEngControls2_9_1of3.JPG
http://www.therangerstation.com/tec...es/Diagrams_ElectronciEngControls2_9_2of3.JPG
http://www.therangerstation.com/tec...es/Diagrams_ElectronciEngControls2_9_3of3.JPG

Power is always present at the injectors connectors (with the key in Run) and the PCM pulses grounds.

You may have a bad PCM relay if your CEL is on with the key Off. Might also be an ignition switch problem.

Wouldn't it flood the engine though if there was always power going to the injectors with the key in run position? I thought the computer needed a signal or something from the distributor's hall effect sensor by way of TFI to fire the injectors.

 

[BillupsOMally]

He said "the PCM pulses grounds", meaning the circuit ispower-load-switch-ground) instead ofpower-switch-load-ground). So you should be able to get a voltage reading between the + injector wire and ground (NOT - injector wire) with KO.

Part of the problem with the aforementioned Honda was that the battery tested good on the Snap-On load tester, but wasn't good enough for the Honda. Dropped in a new battery and solved 80% of the issues. I don't think Fords are that picky, I've boosted mine with a flat battery off an idling Civic. However, if you have a battery charger wouldn't hurt to charge it up overnight then boost it in the morning.

Edit: The Honda would turn over strong and spark but computer wasn't firing injectors on the good-ish battery, so just because it's got enough juice to turn the starter doesn't necessarily mean there's enough left over to run the rest. lol

 

[compaqeo]

Ok so i checked the harness no breaks...has 12 volts at one side of the injector plug. I tried a self test for the ecm...nothing? no blinks. Tested the TPS and its all over the place so going to order one of those tomorrow. Holy crap 2am, okay today i guess haha...Then im going to test the MAP and TFI if i can figure those out...Also how do you test the relay to see if its bad i was going to just pop the top off and push the thing down but cant get the cap off the damn thing.

 

[RyanL]

Ok so i checked the harness no breaks...has 12 volts at one side of the injector plug. I tried a self test for the ecm...nothing? no blinks. Tested the TPS and its all over the place so going to order one of those tomorrow. Holy crap 2am, okay today i guess haha...Then im going to test the MAP and TFI if i can figure those out...Also how do you test the relay to see if its bad i was going to just pop the top off and push the thing down but cant get the cap off the damn thing.

The TPS "all over the place" shouldn't effect the "startability" just driveability; as long it reads somewhere around .9 volts when closed, it should start with it closed at ~.9 volts. Obviously you need a new one, but I doubt that is your starting problem. What relay are you going to test out, the fuel pump relay? You already know that it is good because you have fuel pressure at the fuel rail. The MAP is hard to test from what I can gather and the resistance tests for the TFI are inconclusive (at least they were in my case). I came to the conclusion that my TFI was bad or going bad because when I revved it to somewhere around 2500RPM and held it there, the timing seemed to be jumping around a little instead of holding steady at 20* or whatever. I've never heard of the injectors being so clogged that it wouldn't start although I guess that anything is possible, but I'm leaning more towards a bad ECU or wiring. I thought I remember seeing somewhere that there are several grounds for the ECU, be sure to clean them all up and reconnect them. I've worked on so many vehicles over the years, but I think that I remember seeing a fusible link or maybe an inline fuse on one of the ground wires for the ECU and it was somewhere near the battery. I could be mistaken about that one so maybe someone else can confirm or correct me.

 

[compaqeo]

The TPS "all over the place" shouldn't effect the "startability" just driveability; as long it reads somewhere around .9 volts when closed, it should start with it closed at ~.9 volts. Obviously you need a new one, but I doubt that is your starting problem. What relay are you going to test out, the fuel pump relay? You already know that it is good because you have fuel pressure at the fuel rail. The MAP is hard to test from what I can gather and the resistance tests for the TFI are inconclusive (at least they were in my case). I came to the conclusion that my TFI was bad or going bad because when I revved it to somewhere around 2500RPM and held it there, the timing seemed to be jumping around a little instead of holding steady at 20* or whatever. I've never heard of the injectors being so clogged that it wouldn't start although I guess that anything is possible, but I'm leaning more towards a bad ECU or wiring. I thought I remember seeing somewhere that there are several grounds for the ECU, be sure to clean them all up and reconnect them. I've worked on so many vehicles over the years, but I think that I remember seeing a fusible link or maybe an inline fuse on one of the ground wires for the ECU and it was somewhere near the battery. I could be mistaken about that one so maybe someone else can confirm or correct me.

I want to test the computer relay. i guess im going t check to the computer grounds again i guess