ilovefords31

I have 86 300 i6, and I am having a very hard time getting the timing set. The main reason is the timing mark is completely gone so I am trying to time it by ear right now. So I have been turning the distributor a tiny bit at a time, and then test driving. No matter where I put the timing, when I go down a hill and let off the gas pedal, I get a pop, pop, pop, pop, from under the hood, sort of like backfiring. But I only hear it when I let off the gas, but my hearing is not that good so it could be doing it always when I let off the gas, I am not sure. I am really depressed over this because I have nobody that can help me with this kind of thing, and I cant figure out what to do. All the wires and plugs are just over 1 year old, and that is pretty much all ive changed in the ignition system. Please help me!

Good old Bill

Its common for a carburated engine to load up on fuel during deceleration and cause popping in exhaust.

Remove #1 spark plug and use a wire to locate TDC thru plug hole. Mark your balancer at pointer, this at least will give you a reference where 0 is.

ilovefords31

Thank you Bill. I did get the timing squared away this morning. I sand down the balancer with 80 grit, and found the line. Beiieve it or not I had it set a 10 btdc by ear. But I was wondering, can a bad EGR valve do this? The reason I am asking is because it has never done this noise before yesterday, and I had to repair the black plastic hose that feeds into the EGR valve, and I was thinking it might be leaking because without the connector I just have it sitting in the vacuum hose. Could that be a problem?

Good old Bill

EGR = Exhaust Gas Recirculation. EGR is only supposed to be functioning while the engine is running, not at closed throttle operation (idle). The usual failure of EGR is, the valve hangs up and the engine quits at stops. I find it hard to believe a malfunction of the valve can cause the noise and not have the engine quit at stops. I have never heard of this happening. Engine quitting at stops, yes. Noise, no.

I still lean towards to much fuel being dumped into the exhaust.

ilovefords31

Bill I rebuilt the carb over the last couple days, and now I have the low idle screw all the way in and the engine will hardly stay running. I am stalling out at stops now. I believe the sound I hear going down hills is the engine trying to stall. This is extremely aggravating!

ilovefords31

I unplugged the tps and the idle went up a little, and now the popping sound, and the stalling when coming to a stop is fixed, but, the idle is still low, and I have the screw all the way in. Does this mean the tps is bad, and would a bad tps do that to the idle?

ilovefords31

Also when I rebuilt the carb, the instructions told me to bottom out the needle valve, then turn the adjuster one full turn. This is way lower than it was originally. Could that cause the idle being too low? I also have very little power going up hills. I had it floored and only hit 35 going up a moderately steep hill. About 35 degree angle or so. But for some reason it also was not kicking down to second gear, so this was in 3rd gear. Please someone help.

ilovefords31

bump

ilovefords31

ok so I ran obd1 test, and I got the following codes.
Engine off, Key on
23, 10, 14, 51, 63, 13.
23 TPS out of range
10 Nothing
14 Ignition Profile Pickup (PIP) circuit Failure
51 ECT Sensor out of range
63 TPS Circuit fail
13 RPM Idle out of range idle to low

Just want to say I have ran the truck with these sensors disconnected for testing purposes, I don't know if that caused some of these codes. If someone could tell me what these mean, I would greatly appreciate it.

Engine Running
23 TPS Out of range
41 Hego Ho2s Sensor Voltage Low System Lean
Then I was supposed to hit the throttle, but I did not know that so the test was ended at this point.

Good old Bill

Lets see if I can help out here. The EEC IV system as Ford called it, is performed as such. Start engine and run at 2000RPM for 30+seconds. Shut off engine, wait 10 seconds and turn key to ON and turn tester on, first code received is called a hard fault and that is definitely a no-no. Then comes, I stand corrected, first comes a code telling you the engine category, 20 meaning 4 cylinders, 30 meaning 6 cylinders, 40 meaning 8 cylinders. This has probably gone bye-bye with the OBD I classification. So lets start over, your 23 is a hard fault (TPS out of range) then the 10 (that's when you goose the throttle, pump the brake, and turn the steering wheel). After the 10, the computer goes into memory and displays the codes during the last drive cycle. Unfortunately, if the engine is not up to normal engine operating temp during the retrieval of codes, a code is printed pertaining to improper test procedures during the goose test time (code 10 signal)

Your codes: 23 a hard fault (TPS out range)
10 (the spacer signaling goose test, PS pump test, and BBO or
brake booster test
14 PIP
51 ECT (engine probably not warmed up sufficiently)
63 TPS (throttle position sensor)
13 RPM (idle out of range)

Your engine running codes is again a repeat of a hard fault 23 (TPS) and a new one: 41 (HEGO not warmed up during the test).

PM me if you have any questions.