I've been trying to get my brothers truck running with little sucess. It is a 2.9 L V6 Ford.

Here is a list of the tests we have run and the results ;
-Compression check: (with cylender numbers)
1- 97psi.
2- 84 psi.
3- 13 psi .
4- 109 psi.
5- 86 psi.
6- 48 psi .
-Timing (dristrubutor), reset at 10* advanced (hane's manual specific, used light).
-Spark plugs, wires, cap, rotor. (all replaced and double-checked on position).
-Coil: Replaced with new.
-Fuel Pump: 47psi at fuel rail (installed 3 weeks ago).
-Timing Chain did not jump (inspected at Ford dealership).
-Fuel Injectors, cleaned and tested (perfect resistance, not sticking).
-Fuel Filter replaced.
-New air filter.
-Diagonis port check (computer). Puts out no error codes.
-O2 sensor replaced.

What else could it be? It only fires when the motor is cold (once a day after that nothing just spins). Runs with a really lopey idle if any and will not idle on its own (you have to hold the throdle body open all the way to get partial idle).

I'm thinking its just time to give up on this motor and start to swap in the other motor he has up there (good compression in this one (within 16 psi of each other and runs good, its in a 1986 ford bronco 2 (the exact same)). The only problem is that it is an automatic (the trans is out in this vehicle. The only thing I am wondering, are the flywheels different on an automatic and manual transmission vehicle or do they have the tapped holes for both the torque converter and the clutch assembly?


Thanks for the help anyone can offer , I'm stumped
Hybrid STE

hello,you should have between 100 and 125 pound per square inches of pressure on each cylender with aprox 10 p.s.i. difference between the highest and lowest cylender.youre readings are very low,recheck with another gage and if you yeld the same results,this engine will have to be rebuilt or replaced.also if you shoot some oil in each cylender and the pressure goes up,then this is a good sign of ring/cylender wear.hop this helps.fohldmon

Automatic trans equipped engines don't have a flywheel. The have a flex plate instead. Really enough material for the torque converter to hang on and to keep the teeth there for the starter to grab.

You know, I have a Honda 185S trike that had the same problem. I found that the head gasket was blown. Not sure, but maybe this could be your problem.

I spent about 3 months trying to get an 86 bronco II 2.9L to run right, I finally got a brekout box to check the computers voltage I was getting 3v to the computer....It was the ground to the computer! without a good ground the computer is all kinds of confised. There is a fuse off of the negative battery terminal that goes straight to the computer. CHECK IT, and check ALL grounds I ran a new ground wire to the computer and all my wierd puttering problems went away, and it ran like new. To get proper initial timing Make sure you remove the SPOUT wire from the distributor, otherwise the timing is set by the computer. Here is some good info on the TFI ford module.

Although your lope sounds like its because of your weak compression on #3 and 6


http://www.therangerstation.com/tec...Diagnostic.html

Good luck!

It could be a head and/or head gasket problem. A dead giveaway is when you crank it up, if theres a very quick pressure build-up in the radiator hoses, then its blown between the cylinder and the water jacket, in which case its probably also losing a lotta coolant, but isnt leaking underneath. If its the rings, it should be using a lotta oil. You may check the oil and see if theres water in it also. Is it losing coolant or oil at all, and if so, is it leaking underneath, or just "disappearing"?

You didnt say how many miles on it so i am assuming a lot. If those compresion readings are real you have a seriously worn engine, blown headgaskets or a couple of burn valves. All the cylinders look low but you have a couple of reall bad ones. I think it was 3 and 6. If you have another engine it may be time.
I dont think you once a day start it related to low compression but I would not put any more parts into that engine until you find out what the issue is with the compression. If you have a cooling system presure tester or have access to one, I would put some presure on it and see if it holds. The real bad cylinders could be a blown head gasket. Most of teh time it is better to just swap the engine than to start trying to rebuild the top end. You will have nice compression that the lower end will be to worn to handle.

Good Luck

You said "injectors cleaned", but how? Removed and cleaned by a shop? Did they flow test them or actually see gas coming through the injector?

If they are, then OK.. If not read on =

Will it run when you spray fuel directly into the throttle body?

FYI
Lopey idle, WOT to keep it running sounds like this problem.

If it does run with spray into the throttle body, The injectors will check OK electrically, click when you are cranking.

Today's gasoline deteriorates quickly and will plug the injectors if left sitting for more than about 3 months. You will have to remove each injector and spray carb cleaner in them. If no fuel is passing through them, the standard injector cleaning methods will not work.

If it runs sometimes, or barely runs, I would (drain the tank) have about 3 gallons of fresh fuel in the tank and add 4 bottles of FI cleaner... enough for 80 gallons of fuel. Jump the pump relay and let gas circulate through the rails for 30 minutes and then try to start the engine. If you have to keep it running with the spray in the throttle body do that and keep it running it will eventually clean out the injectors in 10-20 minutes.

Been there, done that.


www.readershotrods.com

check and label all of the plugs as to which cylinder they came from, if the 3 and 6 cylinders are clean and white, you got a head gasket problem, antifreeze cleans them up nicely, so this is a tell tale sign of a head gasket problem

stopped up exhaust.

It does have the sound of a blown head gasket, although a restricted exhaust could create a similar effect. I wanted to make a comment about blown head gaskets. NOT every blown head gasket will leak into the coolant, they can sometimes just blow between cylinders. That would create a low cranking pressure. It would seem that it should still start and run even if poorly. This is a different strategy than the others, but you may have some wiring problems or even an ignition switch. I had an '89 5.0 Gt that did the same thing. It took some checking, but I located a fusible link in the wiring that ran by the brake booster that had been chaffed and it burned through one day when I went to start it. I had the advantage of seeing a small puff of smoke and traced it by smell to the area and located it after checking the wiring bundle.