78 starts and idles but stumbles and backfires.

[zachmac]

I have been trying to help a friend get his 78 Spider back to life. it quit running a while ago and he thoughtit moght be the pickup (original dual point long gone, 79ish breakerless ditributor on car). Replaced the pickup and the ignition control module. He wasn't getting any power at the coil, but after a quick rebuild of the ignition switchand making sure the wires were all plugged in tight at the back of same it starts and idles.

BUT, any attempt what so ever to give it gas causes it to stubmle, backfire through the carb and die. Ideas? Also just put ina new rotor as his old one was cracked. Used a good spare I had liying around and it can only go on one way, square peg square hole, round peg round hole and all that.

Is it possible the dist. cap is on 180 out? Would it start and idle? Is it necessary to re-time after changing out the pickup? I did set the pickup gap as best I could, halfway between the 20 to 24 thousands spec at 22.

I'll go back and check timing later tomorrow but looking for ideas.

[vandor]

Check to see if the accelerator pump squirter is squirting gas when you open the throttle. Do this with the engine off so you don't get your eyebrows burned off by a backfire
If it does not squirt gas then the engine is going lean each time you open the throttle. Might be able to rev it up by opening the throttle very gradually.

[zachmac]

First, sorry, its a 76, not a 78 but with the later dist. and an electric fuel pump not much different.

Vandor,

Thanks for the tips, I'll check btu I think it is getting gobs of fuel based on the white plumes of vapor on backfires and the hole the really big backfire put through the sponge air filter (now removed untilwe sort this out!!).

I'm thinking more like spark / timing related. I had an expereince a few years ago when I put the magnet under the pickup in my 80 in backwardas and it did the same thing until I figured it out! Vandor, my friend sourced the new pickup from you guys and I wasn't there when he installed it. is the magnet attached or can it be put in backwards? I di make sure it was gapped correctly.

[vandor]

The magnet is attached at the correct orientation out of the box, but it is possible to remove it and flip it.

Have you checked the timing with a timing light?