I'm having a strange problem with my 1986 305. I've been having problems ever since summer started. it dont start so well, even after its been warmed up. ever since its been feeling like the engine has been "power surging" slightly. it was hard to tell at first cuz the roads around here are so bumpy. but it got alot worse yesterday. it sounds like it misses. I guess my questing is, do I need a new module? or cold it be just the plugs? or maybe even the coil?
07-19-2005 02:32 PM
It could be the fuel or spark system. Lack of fuel can cause missing and surging. Check the fuel filter and the fuel pressure. Go over the entire ignition system, do a spark test, if the spark is yellow then it`s weak, you should be able to track down the problem from there.
07-19-2005 04:59 PM
Sounds like it's running lean to me. Check for vacuum leaks, this will make the car feel like it's missing as well.
07-19-2005 11:51 PM
Check your distributor connections. If this has the large weatherpak connector coming out of it towards the passenger side, then it is early computer timing control. I have had several of these, all 86 305's in p/u's, come into the shop for tune up. Also, look on the passenger side of the block behind the starter for a knock sensor. If you have these two things, I would be willing to bet that your timing control in the computer has gone south. The begger will chug right down, have no power, and sound like a couple plug wires are off, as well as start crappy and begin to run hor. The early computer is goofing up and whacking a huge chunk of timing out of it. It's an easy fix, just swap in a distributor from a SBC a couple of years older, and on the power wire to the distrtibutor, unplug the lead going over to the harness leading to the pass. firewall. Then plug in the single lead you have left. Re-set timing as normal.
07-20-2005 04:35 PM
allright heres what i did, I adusted the timing a bit. its been set retarded (turned clockwise) for the longest time. I set it so it idles smooth. runs good like that. but has spark knock like crazy! it will only stop knocking when its advanced like that, and it runs rough cuz its advanced to far. this block in a plane jane block, I rigged it up myself with the simple wiring and all that, no sensors or computers on this engine. btw, I dont have a timing lite I just have to do it by ear. I got about 100 spare distributors maybe I'll just change them around.
07-20-2005 04:45 PM
i agree with doublevision it is probably a sparkplug wire breaking down.
07-20-2005 05:26 PM
Yea, I'd also go with double on this one. Sounds like bad spark plug wires to me depending on when you last had them replaced if any at all. It could be possible that one of the has been rubbing up on the headers and burned through. You might want to check out your spark plugs as well just to double check if they're still adequate.