I have a 1990 Tracker Hardtop 1.6 8v 5 speed 4x4

I am experiencing backfiring alot between shifts and when I am off the gas while in gear.

I have a 3" cone filter intake and a removed cat and low restriction muffler.

frankly I am puzzled.

thanks guyz

I have a 1990 Tracker Hardtop 1.6 8v 5 speed 4x4

I am experiencing backfiring alot between shifts and when I am off the gas while in gear.

I have a 3" cone filter intake and a removed cat and low restriction muffler.

frankly I am puzzled.

thanks guyz

First, I'd check for air leaks in your exhaust system and then look for vacuum leaks in your intake system. But I bet you have a couple holes in your exhaust especially if your 'backfiring' is the bang-ba-ba-bang-bang as you're slowing down using engine compression.

HTH, -Eric

I get some of the ba ba ba ba

but other times it sounds like a 12 gauge!

Maybe you pissed someone off and someone is actually trying to shoot you with a fairly large shotgun?

Check the spare tire to see if it has any holes in it....

I get some of the ba ba ba ba

but other times it sounds like a 12 gauge!

Hmmm, maybe something else. When's that last time you serviced the ignition system? Maybe poor spark? How does it run under acceleration? Is it herky-jerky or smooth?

Anyone else have some ideas?

-Eric

rev up fine.   it has a accel super coil...

new cap, rotor plugs and wires.

Vacuum leaks have always been the cause of backfiring in all my vehicles, especially samurai's.  but i haven't had a kick backfire on me before.

i dont know that much but wen mine back fired,

The garage said that it was the timing?

I had a Mustang once that did that after I gutted out the converter. It had an air injection hose connected to it so I disconnected it and it stopped.

I would say you have an air leak in your exhaust system.

Bill

i dont know that much but wen mine back fired,

The garage said that it was the timing?

That's where my money would be.

Two -- make that three -- causes come to mind: 

1. The hold-down bolt on the distributor has worked loose causing the the distributor to "migrate" out of position.

2. Vaccuum leak on the distributor advance.  (This assumes there is one.  I am not sure if the 1990 8-valve was "computerized" enough for electronic advancing).

3. (shudder!) Check the harmonic balancer pulley.  Is it loose or wobbly?  If so, you may have a wallowed keyway that is causing the crank timing belt gear to get out of position enough to cause bad timing.

I hope it is not #3 and if it is, I hope you caught it in time for a JB-weld fix instead of a crankshaft replacement...

I hope this helps!

well I check the timing and it is set at 8^ advance and the exhaust is sealed up and the engine has no leaks. the crank pully does look like it is out of round. kinda wobbly.

whats the fix? new pulley? or new crank

if it's wobbly check cam timing. There is a chance that the pulley is loose and the timming still is correct , but if you are experiencing backfire probably the problem is over there. Even though there should be some considerable play on the pulley to affect timing. Or not?

well I check the timing and it is set at 8^ advance and the exhaust is sealed up and the engine has no leaks. the crank pully does look like it is out of round. kinda wobbly.

whats the fix? new pulley? or new crank

First, get a mirror on an extension and take a look at the front of the harmonic balancer/pully assembly.  You should see 5 small bolts around the large bolt that holds the timing belt pulley onto the end of the crank. 

If the 5 small bolts are loose or missing, then you need to replace them ASAP.  No major damage is done.

If the big center bolt is loose/missing, you need to fix it immediately.  The best thing to do is to remove the timing belt cover (remove fan assembly, the 5 small bolts on the harmonic balancer, remove the harmonic balancer, remove the timing belt cover and remove the big Crank bolt (if it is loose) and then inspect the key, keyway and the timing belt pulley on the crank for damage.  If the damage is not too bad (that sounds like the case) you might be able to fix it with a bit of JB Weld.

Hope this helps!

I would put a factory cap on it not one they had at the locale auto parts and then take your big coil off and put the stock one back on for a test, if you have any moisture in or on the cap or your wires are touching each other it could be cross fireing.

The only time my Trackers ever backfire when letting off the gas is due to tiny exhaust holes. Even a pinhole is enough to do it. When you're on the gas, the exhaust is flowing along fast enough so it doesn't cause a problem, but the flow causes fresh, cold air to be sucked into that pinhole due to the venturi effect(look it up;)) when you let off the gas, you get a sudden surge of cold air that doesn't get blown on down the line. It accumulates in the hot exhaust pipe and readily ignites any unburned fuel, causing a backfire...