sr20det ignition problem

hey, so i have a sr20det with bolt on mods. I’m having this problem of misfiring/car acting sluggish after its been warmed up and driven hard…probably about 30-45 mins and it misfires really bad, the thing is i have switched out my ignitor when this problem happens and my problem goes away instantly! but once again after driving for 30-45mins the problem comes back.then i can put back my other ignitor and the problem goes away once again. so its obviously not a bad ignitor. what could it be ? my ignitor isn’t getting hot at all… i’ve checked all the wiring and grounds. should the back of the ignitor which is metal be grounded? lets here some ideas! thanks.

Plugs fouling, bad coil pack, bad plugs. Sounds like a bad coil pack but the plugs are cheaper so i would check/change them first.

Ussually if it happens when the car is warm there is a good chance its a bad coil pack if you have never changed them they might be over 15 years old.

ya, i changed the plugs already, same problem. i haven’t had a chance to swap out the coil packs…i do have an extra 3 at home. just not sure which one is the problem? and swapping out the ignitor and having my car run good for a bit is just a coincidence? i’m just curious…i’m going to try the coil packs tho, thanks. and is there anyway of testing them?

I had the same issue.
Turns out it was my fuel pump failing out.

i wish it was my fuel pump. it was replaced last year ( only has 10,000km on it, if that ). its not leaning out at all, says my afr, its running rich. i believe this is definitely an ignition problem. going to get the other set of coilpacks in tomorrow and see if that solves the problem.

With the car running just unplug each pack one at a time and then plug it back in before moving on to the next one. If the idle dosent change when unpluging a pack that one will be bad foe sure. You might have to change them one at a time and go try to simulate the condition in which the car runs poorly. They are not hard to get at so it shouldn’t be hard to check them. I hope it is something simple like this. Good luck.

I’m having this very same issue right now with my car too… used to misfire really badly when warmed up, turned out I had 2 coilpacks with hairline cracks in the plastic. I replaced all coilpacks, all spark plugs (and gapped them at 0.8mm) and the problem still occurs once in a while, but just like you, only when the engine bay is hot.

If you find a cure to this issue, please do post it!

I’m going to try to replace the coilpack harness next.

hey, well i had a bad ground before and the problem used to be way worse. now it only miss fires under load…idles like a champ, cruises fine. I’m planning on swapping the coil packs out, just been very busy. its odd tho that swapping out my ignitor cures the problem for 30 mins or so…ill keep everyone updated! thanks so far.
oh and does anyone know if the back of the ignitor ( which is metal ) needs to be grounded?

the ignitor bracket doesn’t need to be bolted to the car for it to work.

well i swapped my coilpacks with a different set, same problem. my ignitor is getting HOT and when it does my ignition starts to break up, i put in a different ignitor and the problem goes away, until that one gets hot. so whats causing my ignitor to get hot to the touch? i’ve checked all ground…grounded the ignitor too. is it possible my alternator is cranking out too many volts? open to any ideas, thanks

alright, well i dont want to speak too soon BUT i think i may have solved the problem. apparently guys down south will attach some sort of heatsink to the back of the ignitor because their ignition will start to break up once the ignitor gets hot. so i ghetto rigged a heat sink for now and i’ve yet to have the problem. and for silvias the bracket that the ignitor attaches to acts as a heat sink…not sure why some people can just have their ignitor hang there and have it work fine tho…but none the less this solves my problem!

how goes the heat sinking? still working?

i guess this makes sense… my car started to have this issue right around the time i lost a downpipe bolt, and had hot exhaust leaking directly under it… i’m also not running a heat shield on the exhaust manifold…

hey, ya its working great. its just temporary for now until i find a proper heat sink for it and can attach it properly…right now its ghetto taped hah. feels good to have the car running properly again. couldn’t solve this problem last year either!

awesome… good to hear. i think i’m going to rip one of the CPU heat sink’s off one of my old computers and try that.