89 Ranger 4cly.

Which one is right, Chilton or FTE. Here on the forums,https://www.ford-trucks.com/lc/lc.ph...jection.com%2F it says Code 48 is "Loss of IDM, left side." In my Chilton manual, it says it is a bad Oxygen Sensor.

I replaced both, and still get the error. Also replaced the plugs and wires. All parts are new. I have checked and cleaned all the connections as well. I cleared the Long and Short term memory, and it instantly comes back.

 

Forget the Chilton's. Two other sources agree with the Ford Fuel Injection site you linked to.

"Loss of IDM" refers to the Ignition Diagnostic Monitor signal that is sent from the TFI module to the computer. Is the TFI module what you replaced?

 

I replaced it with one that was on the shelf, it was a used one Ihad, but should have been good. I hate to spend $150 to find out it was not it. I will have to see if I can get it tested.

 

if you are going to replace the TFI module do yourself a favor and replace the stator too.
Ed

 

All this new computer related sensors and such are fairly new to me(Old Iron Man), but isn't the TFI Module related to the Distributer. The one I have has the Dual Coils, with out the Distributer.

I have been doing a little reseach on the Internet(at Work) and I find a lot of problems associated with bad grounds. I will say I can not rule this out as I just took a two wheel drive ranger, switched the body to a 4X4 Long bed frame, used my shortbed, then lengthened the cab 8 inches, and needles to say, converted it to a four wheel drive.

I did keep all the original as far as engine, wiring, sensors. It is a different Trans though. It should have been a simple plug and play. Proper ground on the other hand, I will not rule out. I know the ground is important to the new systems, and was suprized to see the engine to body ground just dangeling on the back of the engine when I pulled it. I did re-connect it when I put it in the new setup, but I did not really check the battery to body ground.(already connected)

 

All right, I give up, I am not above admiting I am lost when it comes to computer controlled. I have been a Mechanic my entire life, but this is all on older outfits without the computers. I do not beleive in butchering a job, and I want it right.

89 Ranger with the 2.3L Engine. Distributorless Ignition System.

Error Code 48 Loss of IDM, Left Side.

Anything above Idle, under load only, it Coughs, chokes and tries to die. Blows a small amount of black smoke, and the Gas Milage is down(stands to reason) If I keep it reved out as I go through the gears, it runs good. Anything in-between Idle and reved out(under load only), it coughs and chokes.


I have gotten several ideas as to what it is. I have replaced the Oxygen Sensor with a used one, then a new one. New Plugs and Wires. I have no problem with replacing these as they are disposable parts, and needed it anyway. I have pulled all the plugs, and cleaned the terminals, checked the harness as best I can without trearing them apart, and nothing.

True I swaped the engine and body from one frame to another, but all I done was unplug some harneses, and plugged them right back in again. Before the swap, I never had this problem.

My Chilton Manual does not specify how to troubleshoot IDM problems. If I understand correctly, TFI is only associated to Distributor, and this one does not have it. If IDM Stands for Ignition Diagnostic Monitor, then I assume it is Electronic as in Spark or timing. It starts great, and runs great in Neutral, but under load, it craps out. I hook up a timing light to check the spark, and it never misses a beat on either side(coil).

I can only assume now, it is Injectors or something. Before I go replacing a bunch of parts, a idea in what direction I should go/test would be better. I need to learn this.

 

Well, I have a Taurus SHO with the crank trigger ignition (no distributor) and it has a TFI module right on the intake manifold...

But if this setup worked ok in another vehicle and the problems started after the change over, then it almost has to be a bad connection somewhere.

This tip may not apply exactly, (different connectors) but look at this and browse around the site as well, a lot of good EFI info there.

 

I would not rule out the connections as I was getting some error codes that just did not make since, and cleaning and re-greasing the same two connectors(on Fender well on Ranger) cured all but the 48 code. I thought about using an Ice Pick and tweaking the female end as the male end is Solid (no pune inteneded )

I will give it another shot, as it does sound right for what I have.

The one thing that keeps throwing me is the Loss of left side. Am I too assume it is refering to the coil, or becuase it is the 4 cly, then only use one bank of Injectors, so they say left side.

 

You have the dual plug heads, right? So, there are two coil packs and a bank of plugs for each side, and I believe that each coil pack fires the plugs for one bank. Left side is intake, so it should be referring to the coil pack for the plugs on that side.

 

That it what I was thinking, so that is where I have been concentrating. I will not have time to play with it again until this weekend, but I will re-check the connections. I am getting good spark from the Coil, so I assume it has to be one of the connectors.