had number 8 injector replaced at dealer after rough idle problem. ford said number 6 injector was swapped for number 8, number 8 having a longer dwell due to its location on the fuel rail.

trucks runs ok now but milage went to crap, also requires more cranking to start.

dont know if ford messed with computer or timing but the milage wasnt that great ( 10-12 mpg) with a partially, then fully clogged injector, now with a a new one , its even worse.

any similar experiences ??

any suggestions ??

 

most common fuel loss is up pipes leaking..IC boots leaking..and EBPS tube plugged..of corse the right foot has something to do with it as well..

 

I'm a little confused. You needed a new #8 injector so Ford swapped it for the #6? Did they replace, rebuild, or clean the old #8?

How many injectors did they pull out and did they put new O-rings on when the re-installed the injectors?

 

Did You happen to have the recall done on the CPS just shortly before they diagnosed the bad number 8 injector? Randy

 

as a matter of fact they replaced the cps on a recall at the same time they "fixed" the injector. about 6 months ago i replaced a dead cps and havent had any probs.

as far as injectors go, the number 8 was bad. on further inspection they determined that # 6 was a longer dwell injector and number 8 was a standard. according to fomoco 8 is farther along the fuel rail and needs longer dwell to compensate for lower rail pressure. 6 is supposed to be a standard dwell injector. somewhere along the line, either the previous owner or the factory had swapped them, intentionally or by mistake.

i've put 100,000 miles on it the way it was and told ford to replace # 8 with the same type of injector it had in it. figuring if something has lasted the last 100,000 miles it would have broken a long ago or will last another 100,000.

yes they replaced the o-rings on the new injector, they never pulled # 6 they could tell by looking, i guess.

 

2danglong,
Not saying this is it but I've read about several people having problems with their number 8 injector right after having their recall done on CPS. They Immediately have problems and the code reader refers to Inj 8. Most of the dealers are not aware of this yet and start chasing problems. Some of the truck owners suspect it has to do with CPS so they put back in their old Black one and no more problems. Randy

 

I had the cps replaced a few months back and have had a drop in fuel milage especially pulling a load. checked everything else and found no 8 cylinder not passing contribution test. Figured no 8 injector was going bad. Found other people having same problem after replacing cps so I pulled the back up sensor out of the glove box and installed it. Checked contribution test and low and behold no 8 now passes and no 3 also improved. I think it's a scam for ford the sell a lot of injectors in the next year to everyone who does not now about the sensor problem.

 

I had the cps replaced a few months back and have had a drop in fuel milage especially pulling a load. checked everything else and found no 8 cylinder not passing contribution test. Figured no 8 injector was going bad. Found other people having same problem after replacing cps so I pulled the back up sensor out of the glove box and installed it. Checked contribution test and low and behold no 8 now passes and no 3 also improved. I think it's a scam for ford the sell a lot of injectors in the next year to everyone who does not now about the sensor problem.

 

Hey fellas i have the same issue ford did the recall on mine and then the truck vibrated real bad and the computer flagged injector 8, i scramble up some money and replaced it, from that day on it shook worse took it back to ford and replaced the injector again, then it still shook took it back and flagged injector 8 and i looked at the IDS and ran the percentage delta and injector 8 had 9% while all the others had one. could it be the cps? now ford is telling me i need a head or a motor i hope someone knows whats wrong

 

Wes,

If you can get hold of an older black CPS swap it in and see what happens.

 

If nothing else buy another Gray CPS from Ford for $30. Not all of the new ones are bad. I don't know why a CPS would cause #8 problems on a CCT, but we've heard of several reports of these types of problems and I'm just not one to believe in a big coincidence.

 

Sonicblue,

Was your backup CPS black or grey?

 

The one the Ford dealer installed was the grey one. I installed a black one from the glove box that was my emergency one. The number 8 cylinder was running a 5.1 when I did my test and number 3 was running 2.1. After installing the black sensor 8 was reading 1.9 and number 3 was reading 0.1. I checked before pulling the sensor. Changed it and ran the test after. I have since found another black unit to keep as a spare. The grey one will be for emergency use only.

 

Thanks for the reply Sonic. I am going to have to go down to the local Ford dealer and ask around about a black CPS.

 

That's great info. Thanks for sharing it. I've got a gray one in mine that I've had since before the recall came out. Never noticed any problems with it, but now I'm thinking I'll do a CCT to see if there are any issues with mine.