Have a Ford 1988 F150 300 4.9L straight six truck that wasn't taken care of and have some issues with it.

Right now the symptoms are engine sputters when you press the accelerator and are in any gear when the vehicle is cold. Once the engine starts to get up to operating temperature it runs better.

I replaced the following because this truck was very over due on a tune up. Spark plugs, wire, dist. Cap., Serpatine Belt, Valve Cover gasket, intake Manifold Gasket, Throttle body Gasket, EGR Valve Gasket, Cold Start Valve Gasket, Oil/Filter.

The other symptoms that this truck was having was it wouldn't run when you first started it unless you kept your foot on the pedal. It's doing better after I cleaned up the Cold Start Valve, and the EGR Valve. I also replace with used parts the TPS, TFM on Dist., Cold Start Valve, and EGR Valve Sensor, with used parts to see if anything change.

I also made sure the timing was correct and it is 10˚ TDC with timing light and the plug thingy taken out during the timing.

I know I was getting a Code 34 and 77 when I ran codes before these changes on KOER.

So possible low fuel pressure?

Jack

 

Just did another KOER test and I'm getting a 21 and 77.

21 - Engine Coolant Temperature (ECT) Sensor Out Of Self Test Range. 0.3 to 3.7 volts(O,R)

77 - System failed to recognize brief WOT during Dynamic Response Test (user error).

When I hit the accelerator to try and do the WOT the truck dies.

When I did the KOEO test firs I got a code 34.
PFE or EVP circuit has intermittently failed above the closed limit of 0.67 volts.
But I didn't get it when I did the KOER test.

Any ideas about the sputtering when cold and accelerating in any gear?

 

please delete

 

You didn't replace the fuel filter?

 

 

Delete the post? or delete the TRUCK?

 

^^^Fuel filter^^^
And if you DID just change it, make sure it's not in backwards. They are one-way flow, but WILL install backwards.

 

Reposted in the correct forum, that was a request to delete the thread.

 

Yes I did change that too, forgot about that.

This is the first time I got a Code 21 by the way.

Jack

 

How do you delete the thread/post. Tried to do it when I first realized I posted in the wrong forum but I'm not seeing an option to delete the post.

 

You can't. It looks like a moderator merged the 2 threads.

If it happens again, edit your post to say "please delete" and use the report post button (the red triangle with the ! in it) to ask the moderators to delete it for you.

 

The horrible sputtering was the ECT gone bad (Code 21). Didn't think that it would be that big of a deal but reading the fordfuelinjection.com web site it's the third most important sensor for the computer. Other than the throttle body gasket was bad and the Cold Start valve was bad also.

Code 77 still any suggestions for this?

 

I'm not familiar with that engine so take my response accordingly

I assume you got that code doing the KOER test? If so, did you stab the gas when the scanner asked you to?