Ok so I pulled the codes off my 1990 f-250 with a 460 and i set a couple of codes for the KOEO test i set a 22,24,26, all codes saying certain sensors out of range, and i also set 87,95,96 in the CM test. My truck will not run does this mean my computer is bad.

 

I forgot to mention that the whole week before it died it would not idle i had to drive 2 footed to keep the rpms up

 

I guess anything is possible, but I would think a bad PCM would not be the first choice. Have you checked for spark, fuel and compression? Spark and fuel are not to difficult and compression is a little tougher. Next, Have you looked up the meaning of the code numbers that you said you read to see what they are trying to tell you? Is this something that happened instantaneously or over a period of time? Was the truck running and then just quit or did this gradually occur over a period of time,i.e., progressively running worse and then quit?

Code 22 is for MAP sensor and Code 26 is for a MAF sensor? Code 24 is Air Charge Temp sensor. Code 87,95 and 96 all being fuel pump related, I might check the fuel pump relay. I think they run about $32 at Advanced if it is bad.




guzzler96

 

how do you check if a relay is good or bad, i can hear the fuel pump cycle on. this problem started as what seemed like a vacuum leak cause the idle would almost stall and then come back, the irratic idle wasnt as bad in gear if that helps

 

I replaced the coil after finding it didnt have spark. i popped the hood after i got it to started and saw a spark arc from the coil to the thing behind with all the vacuum lines and electrical plugs what would cause this spark?

 

I would think your relay is probably good if you hear the fuel pump cycle on briefly and then stop when you turn the switch on. I don't think seeing spark jumping around in there is a good thing. If all your wiring is in tact I don't think you should see any "loose" spark flying around. I don't know if your configuration is like mine,'90 - 302, but in a close proximity to my coil is fuel pump regulator, TAB solenoid, TAD solenoid and the EGR EVR solenoid. Do you have a Chilton or Haynes manual?? If not you can get some info by going to Autozone's website and going into the Repair Info category, put in your truck info and you can view almost a complete manual. You might want to look in the general info. category and get familiar with the different component names and locations.
As to checking the relay I have been unable to find a test procedure , but I was thinking about taking a DVOM(Digital Volt Ohm Meter) to the parts store and seeing if they would let me read the ohms on a new one??
I believe I would attempt to eliminate that "loose" spark first of all. Could be something like a cracked wire sheathing, bad boot on the coil wire,etc. See if can inspect all spark related components for visible damage and maybe try locate the origination point of the spark if you don't see anything right off on the components.



guzzler96

 

i replaced the new coil and the spark seems to be gone, but to keep it running i have to keep pumping the gas pedal which doesnt make since cause efi doesnt have accelerator pumps does it? any help or ideas im open for

 

i pulled the codes this morning and im only setting a 22 now which is the map sensor so hopefully that will fix it

 

I just went thru an extensive sensor testing this weekend. I have an Actron CP 9087 ignition module and sensor tester. Cost about $75 at Sears, but I checked the MAP, ECT, Oxygen, Throttle Position and EGR Valve Position Sensors with it. It will also check Ford TFI ignition modules. What I am leading up to with this is I read a post a while back where someone said Autozone can check ignition modules. If they use a tester similar to or even the same one that I have there is an off vehicle test for the MAP. If they can test it for you it might save you some money. My MAP is the original one that came on the truck and it checked out fine. Glad you got your spark under control.

You might take a vacuum gauge and check your vacuum at the upper intake manifold and then tap into the hose going to the MAP sensor just to verify that you have vacuum at the MAP. If you read between about 17" hg and 22" hg with a good steady needle, not erratic and not sweeping, it should indicate a sound engine. This weekend mine read about 18" hg at idle and as I increased RPM the vacuum would rise. About 21.5" hg at 2200 RPM.



guzzler96

 

i tested the Map sensor out (the way chiltons says too) it had no respons to vacuum so i ended up replacing it and she works like a champ now. thank guzzler for talking me out of a new computer

 

No problem. Glad you got her fixed.

Keep on Postin !!!!!



guzzler96