WizBandit

I just thought I'd share this as I got a lot of good leads from this forum. My 1987 F150 I bought new and has been a great running truck, the 300 I6 is a great engine. About 4 months ago it started "bucking" while running after it was up to operating temperature. I converted it to dual fuel in 2000. The propane computer works with the onboard computer using the O2 sensor and disconnecting the the common wire to the fuel injectors and the +12V to the fuel pumps, way cool, and works well. The fuel pumps +12V is wired through a switch so it either goes back to the fuel pumps or feeds power to the propane cut-off solenoid and the propane computer. I didn't know it had trouble codes that I could read so I started replacing parts, ignition module, MAP sensor and I even took the computer out and even though it was covered in white aluminum corrosion it was okay inside so I sealed it with silicon grease and put it back in. Nothing was fixing it, after it got up to operating temp, the fuel pumps would shut off. I built an LED code ODB reader and got some real trouble codes. One was neutral switch malfunction, I knew about that because I had just rebuilt it as this also keeps the starter solenoid from working. The next was EGR sensor out of spec's and EGR valve malfunction. I checked the connector, it was fine, I pulled the EGR valve off, removed the sensor and tryed to manually move it, notta, carboned up and stuck, a bit of WD40, some carb cleaner and about an hours worth of scraping I finally got it freed up and working. I then disconnect the battery for 30 minutes then tryed to start it up. It ran until it was again up to temp then quit. I read the codes and this time all the EGR codes were gone BUT I had a PIP eratic trouble code, a quick search on what the heck PIP was and I found it was the inductive pickup inside the distributor. For the umpteen time I drove to our local Advanced Auto parts but this time I got to talk with our local master mechanic that works there about my problems. He told me not only does that PIP control the spark but it also tells the computer when to fire the fuel injectors and tells the computer the engine RPM as well. He told me that the computer ignores most sensors until the engine gets to operating temperature and that if the computer was getting erratic pulses from the PIP that it will shut down the fuel pumps thus shutting down the engine at operating temperature to prevent the injectors from operating at the wrong time. I replaced the PIP, fired it back up, runs like the day I drove it home, well, that's the simple version. To replace the PIP I had to pull the distributor, punch out the roll pin in the cam gear, use a gear puller to (painfully) pull the gear off, chipping a few teeth in the process but I did finally get it off. It took all of 4 minutes to install the new PIP and 3 hours to put the gear back on, it was so tight I was afraid I was going to break something. I put the distributor in the freezer for an hour, then I heated the gear with a propane torch, oiled up the shaft and managed to get it half way on with my glove before it seized tight. I set the distributor upright on a block of wood and carefully used a deep socket to tap the gear up where it belongs, but the roll pin hole was off by a bit so I thought I would use a small tappered punch to set it straight, nope. I put a hair-crack in the gear. At this point I said the heck with it, put the oilpump drive shaft back in the bottom of the distributor, put a cresent wrench on it and used a big channel lock to turn it so the roll pin hole lined up. Lost the roll pin with all tapping so had to get a new one, it was 1/4" too long so had to grind it down. That's my story, it's in, it's running and I'm tarred, been under that hood for 3 days straight now. I hope this helps someone...

gearhead

Thanks for the detailed write-up. I didn't realize how much of the engine this piece controls. If mine goes bad, I'll opt to replace the distributor.

Question, wonder if the PIP is replaced in a remanufactured replacement distributor?

Is this a picture of a pip? Rock Auto lists this as a Distributor Ignition Pickup.

gearhead

http://forum.doityourself.com/automo...n-voltage.html