car is an 1990 1g dsm

SETUP 20g at 30 psi on E85
1200cc all supurting mods


I would drive normal on the freeway everything is normal from 0 mph to 75 mph
if am easy on the boost

But if i go full boost to do a hard pull it will make a sputtering sound out from the exhaust and it does it right at 5k afr is at 11.7 to 12.3 and the sound are coming from the exhaust

at first i was thinking its was my rear end but i figured if my rear end was bad it would make noise at 75 mph or 35 mph in witch does not

i checked the plugs and the look normal they kinda look like the have a white film on them but its light

anybody that runs E85 on there dsm come across this issue?
any input would help



TIA

Does it still misfire if you turn the boost down?

Even though the plugs look ok, they could be gapped too wide and you could be blowing out spark. Try gapping them down to .025"

what plugs are they we run br8es in coreys and my car they are a non-projected tip motorcycle plug we use the non projected tips because if you look at the normal bpr8es' after they have beeen ran for awhile the first few threads are black from combustion. the non projected tips dont stick as far into the cylinder helping to evenly burn the fuel mixture reduce hot spots and reduce knock.

I used to always run the BR8ES plus in mine, but I found that I was fouling them out too fast. They were too cold. I went back to BR7's and it works a lot better for me. I'm not sure how running E85 plays into it, since I don't use E85, but I would think you'd want a warmer plug with E85 because it cools down the combustion so much.

I got some bpr6 Hoter spark I'll let u guys know what happenes

Gap Em @ .020 and check spark plug wires, coil pack, cam sensor, wires and all plugs make sure everything is nice and tight no cuts on the wires and check ur battery terminals make sure there tight...Let me Know after all that......................

7's gapped at .020" and your problems will disappear. I had a hell of a time trying to get my bpr7's gapped at .028" from misfiring at ~32psi. Gapped them down to .020" and now misfire went away.

**update**.
I changed the wires and the plugs And I noticed some heat marks on the wire whitish coloration
As soon as the rain stops I'll take it for a drive

*update*

Parts I have changed

new plug wires
new plugs bpr7es gapped at .19
Fp intake

I took it for I drive no missfire Whats was strage is that I never adjusted the boost controller and it went from 30psi to 25 psi boost leak ?? maybee ......

Another issue, I Turned up the boost 4 turns and the boost still around 25~26 psi
also The car makes a miss fire noise at 7k

**update**

I did a boost leak test. And I found a leak at the intercooler cupler side
I'll fix it tomorrow and see I the problem still presist