Can the EPC come on if a misfire is strong enough? I recently changed the plugs and still get a misfire in cylinder #2 so I'm assuming it's the coil pack that needs to be replaced. The misfire is worse now because it happens almost every time boost kicks in. My bad n75 or wastegate is probably making it worse too because boost comes on way too strong when it engages. Losing all throttle response can lead to an accident and it happened twice coming to work this morning.

 

Have you tried unplugging the vac hose on the front of your intake manifold? I know when I lost that hose, I could only boost 5psi, and that would be safer than how the car is now.

Whats the EPC code? Boost deviation?
And have you swapped the coil pack to another cylinder to see if the misfire follows the coil?

Do you have a boost gauge?

 

EPC = Electronic Power Control

THat light will come on when there is a power issue with the ECU.


Have you tried moving coil #2 to another cylinder and see if the misfire follows? If it doesn't move with the coil you might want to swap the fuel injector and see if the misfire moves too.

Have you done a compression test on all 4 cylinders?

 

Thanks for the response. I'll unplug that vac line then before I go home. So that makes the car gpo into limp mode? I have to check if there's an EPC code when I get home. This happened a couple months ago but no cel came on though. This time the cel is on but I think its because of the misfire. I did move the coil pack a little while back and the misfire followed it. I need a boost gauge actually. I really don't want to be dumping more money into the car if I can avoid it because at this point I'm getting tired of the poor reliability of this car and I want to trade it in in about a year if I can.

 

I like your car, and would trade you if I could. I got lucky and have had a mostly reliable car (a couple things came up, but they were age related, and not major)

Plus the tip is so boring.

 

we all like his car but ever since he blew up his engine and swapped it, nothing but issue's for him =[

 

Hey thanks guys. Well I disconnected that I'm vac line and the car runs great, just with less power. I can floor it at any gear/rpm with no issues. So what does that mean? Should I buy that coil pack or should I just get an n75? What if I were to just get a MBC and set it at stock boost? Thanks for helping me out. You don't know how stressed out I get with this car

 

Probably the coil pack is failing due to higher boost, si Id swap it just for safe measure. The correct boost tells me it is in fact the n75 and not the wastegate, which isnt as bad. I think this may be time to do the doide mod with a boost controller (after that boost gauge of course)

 

Ok, I called a junkyard and can get an n75 for 50 bucks and a coil pack for 20, so that's alot better than having to get another turbo and wastegate. I checked the cel after getting home and the only code was P1335 (crankshaft position circuit). Is that caused from a severe misfire? I don't understand why I didn't get another code for a misfire though if that's the case.

To be honest, I could live with running the car in limp mode for a while until I have more funds available. It's better than getting erratic boost and having to pull over all the time to restart the car. I found some vac line caps at the auto parts store and was going to cap off the ends of where the vac line should be connected to the front of the IM. Would I be messing something up by leaving it like that?

Sorry for all the questions, but when you have a MBC installed, does that just override the n75? The whole concept of it is a little confusing for me.

 

That crank sensor code could cause the misfire, it wont be throw because of a misfire.

The MBC can replace the N75, but you still have to leave the N75 plugged into the harness. You can also run the N75 in parellel with the N75 allowing a 2nd path to the WG actuator.