Im really getting fed up here, il try make this short. So about a week ago I had installed my Megan test pipe on my evo 8 and love the outcome, idle seemed fine and car ran perfect. A few days later when it was on idle I notice engine choking but didnt panic and assumed it was no big deal. So about a week in (yesterday) I start the car to warm it up cuz of cold weather and I get a very bad idle (car is at .5 rpm) and is hardly staying on. So I try in half hour and then the car doest start at all!! It clicked that I forgot to plug the o2 sensor in after installing the tp and plugged it back this morning. Turned back on but shortly after it didn't start again. Did I ruin something when I forgot to plug the o2 sensor back in? I'm so confused this came out of nowhere and it all happened in my garage within a week. Also I was running the car with next to no gas inthe tank that week if that helps. But if anyone knows what could be wrong I'd appreciate it. I've checked and double checked map sensor, hoses, piping all seems to be in check.

 

Oh and also the SES light is not on so it's got nothing to do with that..

 

hey guy are u the original owner of te car? would you kno if it had ever been tuned before? just cuz ur cel isnt on doesnt mean there isnt any codes set.
just saying this because there are ways to turn off or simulate rear o2 even when its not there. otherwise there would be a cel. so if you have no idea if the car ha been tuned before and it has. then its a good possibility the rear o2 simulation has been flashed to u ecu and that would eliminate any cel's you would have.

do u use ecuflash or evoscan? id recomend hooking up and checking for any cel's. if you dont have any stored codes you could try to re-flash your rom and see if that fixes anything. your rear o2 shouldnt cause anything as far as idle quality though cus really the only job your rear o2 has is emisions related. meaning the only thig it does is moniture cat efficiency. it turns on your light if it sees your cat taking a crap. buuttt when ur car is on first start up your fueling is determined by your rear o2 until your engine reaches a certain temperature then it switches to you open loop and uses your front o2 sensor. if thats the case and your ecu seen there isnt any input from your rear o2 it might have told ur car to run extremely rich which could cause idle problems. idk if thats your prob but if you find out let me kno.

 

No, car was previously owned by someone in the states I have no clue About history of tuning, I've never used evoscan.. But do you think that could affect me a year after driving? This started happening a week ago. I've owned the car for a year and have not tuned it since. Before it wouldn't start it was puttering out thicker grey smoke and sounded like a lawn mower..

 

clean up IAC, TPS, injectors and use good gas ( i preffer shell 93)
also check for vacuum hose for leaking

i would like you hear you back. ty

 

Okay *UPDATE* so I'm checking The fuel tanks in the back seats when all of a sudden I hear a mediUm quiet ticking noise so I run to the front of the car and determin that it is coming from my intake manifold/ throttle body area..it almost sounded like there was a liquid oozing out of a crack during I pressure..this must be the cause of my problem but I don't know what it is!!! jym89709, could it be the IAC? Camon people I have a feeling I'm close to a fix..

 

If your IAC was bad, you still would be able to start your car and keep it running with your foot on the accelerator (giving it enough gas to stay idling). It just wouldn't idle at all or maybe for a few seconds then turn off....thats how my IAC acted when it crapped out on me.

Are you able to keep the car running if your foot is on the accelerator?

Dumb questions but I have to ask, have you put gas in your tank lately?

 

Haha yes there is gas..but like I mentioned I ran it shortly before this happened with the handle below the low gas line but it didn't run out of gas, right now the gas meter reads just above the line (gas warning light is off) and no when I press on the gas pedal it seems to be doing nothing at all..

 

I'm leaning towards fuel pump failure..do the symptoms add up and does anyone know if it's a common problem in the 8/9's? Plus I can't hear the fuel pump when I try to start it up..

 

Try using an alternative fuel source aka shoot some starting fluid in the intake and see if it kicks on.

 

Good idea I will try that now.

 

**UPDATE** so I tried this last night and what happens? The car almost starts up but then dies down again. What does this mean. Fuel pump? Injectors? I'm almost certain it's one of the two!

 

im concluding that the issue is in fact my fuel pump or fuel pump relay since i turned the key ignition and did not hear the fuel pump activate as usual..

 

Tested the fuel pump separately by taking it out and connecting my 12v battery to pump and it does not activate! It was infact the fuel pump! I'm ordering a walbro 255 if anyone else has my symptoms I warn you it's probably the pump or its relays. thanks for all you're guys help as usual and consider my problem solved.

 

How many miles on the fuel pump?