OK, after a visit to the F150 forum and more troubleshooting I'm back to the injectors again and I think I've found the problem. I tore down the engine enough to get the injectors out and ran them on the test bench where they showed a 10% flow variation in the cycling test. That's definitely enough to cause trouble. Flow rate at saturation is 50 cc/12 sec or 2 oz/14.5 sec and from that I should be able to calculate the size of the injectors. Just a bit of math required and I'll have to dig up the formula for it.

These injectors are a dark OD green, not quite black. Marked XR3E-C5B also
0 280 155 865 and 230422.

Tarajerame if you or someone else can turn those numbers into a flow rate that'd be great. If not, I'll just have to go with the calculations.

JB

 

Two sets of injectors later... On the flow bench the stock injectors came out right at 24 lbs but I had a 10% variation during cycling (part throttle) flow. certainly enough to cause the problem. So I picked up a set off fleabay but they tested over 16%, not helpful. Sent those back and got another set which came out around 3-4% which may be within the margin of error for the bench, it's hard to say. They also got better the more I tested them so that's a positive result. These were dealer take-outs with around 20 miles on them so once they were back in service and flowing good they should be fine. They are purple and full flow rate was identical. I decided to go ahead and replace the FPR (regulator) while the upper intake is off and will get the new one tomorrow.

Then I decided to have another go at removing that one stubborn spark plug. The one where I had a local garage install a swaged thread repair to fix the plug blow out caused by the Bad Ford Robot. This time I snapped the handle of the ratchet and got it broke loose and it came on out though it was snug. Quite a revelation that, a nasty black thing with no ground electrode and buggered threads on the end. This is probably the main cause of my problems. I just hope the electrode blew out the exhaust valve rather than embedding in the head or the piston. So anyway I liberally applied anti-seize to the new plug (Bosch single electrode) and though again snug going in it seated properly with no indication of a problem. I cannot imagine what the mechanic did to accomplish this, but clearly all did not go smoothly on the thread repair. Nothing of mine will ever go back there again. But regardless, it seems all is now as it should be. All new coils, new injectors, pump and FPR, and in short, a major tune up accomplished which should mean the truck is good for the next 120K miles. I will change the tranny fluid, filter and add the Ford additive after the test drive and hopefully that will just be normal periodic maintenance rather than an attempt to fix a problem.

JB

 

Results are in and they are pretty good. The cowl shake is gone and the truck seems to run right well. I still need to change out the tranny fluid, can anyone tell me if these have the drain plug in the torque converter?

Sitting with the battery disconnected reset the ECM of course and after driving it awhile the check engine light came on. I'll have the codes checked and reset in a couple days but I suspect it was out of tune initially and once reset might be fine.

It probably didn't need injectors. During the last series of tests on the injector flow bench the bench's fuel pump failed. So I swapped in the pump I had removed from the Blackwood's fuel tank and got better and more consistent results. After getting the truck back on the road I went back and checked the old injectors again and they showed acceptable flows so they probably would have been fine. But, brand new ones are good too and the price wasn't bad.

JB

 

For those of you following this thread, progress has been made. I just had the truck to the tranny shop and had the fluid changed and additive put in. Two issues remain. I have a code: P0401 (EGR system fault, ECM detected low gas flow) and the mileage is down around 10 mpg around town.

I now have new coils (Accel) new plugs (Bosch single electrode platinum), new injectors (Ford Mustang 24 lb) and new tranny fluid. The major fault was a plug with the ground electrode broken off. The "cowl shake" symptom is gone. It seems to have been from a combination of misfire and TCC chatter.

The EGR code was not there before I pulled the top of the intake off to change the injectors. The obvious thought is that maybe a line was connected wrong but there are few opportunities for that. I have a white vacuum line to the water control valve for the heater which could possibly be switched with a red one nearby (FPR perhaps) but everything else seems to have only one place it could go. So I'm at a loss and could use suggestions on this one. Are there known trouble spots? As for the mileage, well one thing at a time I guess. Thanks for any help.

JB