Thread: Backfire..

Tweet

If isn't one problem it's another.. OK so was about to hit an on ramp for the freeway and I go to "get on it" to catch up at freeways speeds and she backfires through the passenger side exhaust and bogs so I let off the gas and give it a little more gas and it does it again but keeps going well I get her home and start looking around and see that 3 plug wires have been laying on the headers and have cracked. So I buy a set of accel plug wires and a Accel coil just in case it might have shorted out and still does the backfire but now a few pops through the exhaust and one through the to .. Checked the lifters and all seem to be working as they should, only thing I haven't replaced are the plugs and the ignition module and was wondering if they could have gotten shorted out from the 3 wires Arcing?

Using Accel parts, anything bad is possible! (jmo)

Have you ever verified the timing? How about carb adjustments? Have you measured the vacuum in the intake manifold?
So many questions but you'll need to isolate the problem to either carb or ignition. SO there will be some testing / measurements to help locate the problem(s),

X2 on Accel anything

Gah sorry! I knew I was forgetting to add something, but it's a 88 tbi auto 700r4. it ran good before It started backfiring, is it possible that maybe the ignition module in the dist could have gotten shorted or maybe the plugs? Tested vacuum pressure and it seems OK haven't looked at timing, also it runs good and don't miss at idle or when cruising, could be possible it jumped time a little? also should have mentioned this when it does do the backfire, it will do it a few times then after that it won't when I go wot,

I once had an issue with the wires to the reluctor coil (round doohickey with the little triangles in center of the dizzy- has two wires coming off) it was tough to diagnose. I finally saw that the insulation on the wires had cracked. Caused it to short intermittently.

It's something to check, anyway.

It's possible that the bad wires caused the spark plugs to foul badly enough that they will need replaced or at least cleaned to ever fire again.

Ok got too messing with it this evening and might have found the problem! Seems plug 4 and 8 have gotten fouled pretty bad going to change them in the morning and see if that fixes it! Pics below!