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I recently completed a mass air conversion on my 93 f150 5.0. Everything I have read, which was a lot, said that I should be getting 15 plus mpg with this and I'm still getting the horrible 13.5 that I got with the speed density. I have a check engine light that comes on shortly after the engine starts. I haven't been able to find someone that has an OBD1 reader to find out what the problem is. I was wondering if anyone might have some ideas. I'm beyond my expertese on this one. Please help!!!
Thanks guy. I got the codes. Nothing that I think would effect the mpg, except maybe this one; 95: Fuel pump secondary circuit failure. The EEC senses infinite resistance to ground from the fuel pump on the Fuel Pump Monitor circuit. When I did the conversion I didn't wire in for the fuel pump. Everything else was saying low voltage.
g_k, My truck weighs about 6200 lbs. I've got a 6in lift on 35s. This shouldn't keep me from getting no mpg gain. I did have 17.8 mpg once, but haven't hit that again.
Not unless it's a centurion conversion crew cab. Have you weighed it on scales?
Originally Posted by mpjosh2001
I've got a 6in lift on 35s. This shouldn't keep me from getting no mpg gain.
You do have the speedo recalibrated for those tires right? The lift and tires will reduce milage because there is more wind drag and rotating mass so 13mpg isn't totally out to lunch.
I haven't weighed it on the scales. I was just going by GVW. I'm running 3.55s. Correction on the tire size, 32. I know the speedo isn't calibrated, I use my gps. The codes are 51, 22, 95, 23, 54, 34, and 82. Not in that order.
I haven't weighed it on the scales. I was just going by GVW.
Oh.. that's the weight of the truck plus it's rated cargo not the curb weight. The truck itself only weighs about 5000lbs, mine is 4900 on the dump scales with 30" tires on stock wheels, no lift, a tank of gas and me.
Originally Posted by mpjosh2001
I'm running 3.55s. Correction on the tire size, 32. I know the speedo isn't calibrated, I use my gps.
The codes are 51, 22, 95, 23, 54, 34, and 82. Not in that order.
All the main sensors are out of range according to that, looks like you have to verify some wiring. Did you use a kit for the conversion or was this a complete DIY effort? What EEC are you using?
My gps has an odometer on it. The conversion was a diy. What do you mean by verify some wiring? Check the locations on the ecm connector?. The computer is labled A9L. I also have to put my foot on the accelerator to start the engine.
The conversion was a diy. What do you mean by verify some wiring? Check the locations on the ecm connector?. The computer is labled A9L.
That's a mustang EEC so yeah you have to verify some wiring. What did you use as a wiring diagram for this? There are quite a few wires that have to be moved around on the truck harness to make it compatable with the Mustang EEC.. and that's besides those that are added for the MAF meter and sequential injectors.
I used a mustang wiring diagram. I found several articles that told me what wires needed to be moved and which ones go where. I checked, double and tripple checked the diagram before I even plugged the battery back in. I can't afford mistakes.
I used a mustang wiring diagram. I found several articles that told me what wires needed to be moved and which ones go where. I checked, double and tripple checked the diagram before I even plugged the battery back in. I can't afford mistakes.
Well.. something is still wrong or you wouldn't be getting all those codes, maybe a reference voltage wire is missing or misplaced. Here's a nice color diagram for the Mustang EEC you can compare to the others you have,
And here's a spreadsheet I made showing what EEC connector pins that have to be moved.