Around Christmas time I bought my son a 1990 F-150 to drive. He is 17 and it seems to suit him well.

It has the I6 and an automatic.

After the holidays, I put in a new rotor, distributor cap, plug wires (which looked to be the original ones), and plugs.

The air filter was fine.

Changed the oil and filter and off he went. It was running very well. Very smooth.

A week ago the lower radiator hose blew a hole. My son knew that something was wrong and got the truck off to the side of the road and called me.

I had it towed home and replaced both the lower and upper radiator hoses.

Ok, now for the problem. It is generally running rough at idle. Seems to get down the road just fine, but at a stop it acts like it wants to die, but never has.

I took it out for a drive with him this evening and the Check Engine light came on. We stopped by AutoZone and they read 4 different 2 digit codes.

Here is what we could find from a Haynes trouble codes book

32 - EGR not control
56 - MAF/VAF Circuit above max voltage
64 - ACT Sensor circuit grounded or 254 degrees F indicated by ACT/VAT sensor
67 - A/C clutch energized during self test.

In addition, I'm hearing a shrill squeeking like the belt is slipping (which may be the case) after the truck warms up. I'm certain that antifreeze was sprayed throughout the engine compartment including the the belt. Perhaps that damaged the A/C compressor as well.

I can check the fuel pressure if you think that might help.

Your advice is appreciated.

Hunt4Fun

 

First, the codes need to be interpeted in relation to the engine application (4.9L).
Code 32 is EvP voltage below closed limit.
This is a problem with the control switch that controls manifold vacuum to the EGR.

Code 56 TOT (transmission operating temp) sensor circuit ground failure specific to your engine. You don't have mass air.
Code 64 is air charge (ACT) sensor ground or open.

Code 67 is the neutral switch/ manuel trans lever/ A/C input signal either open, grounded wiring.

Sounds like the antifreeze has done some damage.
You need to go ever all these areas to clear all the problems.

 

Bluegrass,

Thanks for the response. I'll check the wiring down to the sensors this evening. If that looks good, would you expect that I should be changing them out?

Hunt4Fun

 

Anti freeze is sticky and does not dry very fast and may be conductive.
I would flush with clear water out of a spray bottle clean/ dry all connectors as well as the sensors and let dry good with engine heat under closed hood conditions.
Keep at this and see if the codes start to leave by canceling the codes and seeing what comes back and keep after the areas that return.
The code cancel is so your not looking at old history after any fault has cleared.