Seems like I've done something wrong here...

I seafoamed the throttle body hoping that would clear up the misfiring problem by cleaning out the injectors. Took it for a drive after the seafoaming and noticed that the misfiring was still happening. Less noticeable, but still there. Not much improvement in all honesty.

I drive it around on the highway for ~10-15 minutes, getting up to about 70 mph. Normal performance, maybe a little better than normal. Car sits for a few hours and I take it out on a trip. And suddenly its abysmal!

Its not misfiring so much, but there is a definite failure to accelerate. Going up a hill I can floor it and still lose speed, the engine refuses to raise the its RPM above 2 - 2.5 Its nuts! Sometimes there is misfiring accompanying the problem, other times it just doesn't work. Its like my pushing the gas down doesn't do anything to the car.

Frustrating turn of events to say the least. I've never driven the car at 65 mph and had under 3k rpms, but this seems to be norm now, except I can't accelerate worth a damn. Its like its locked in and ignores me.

It varies, is inconsistent and is annoying the hell out of me. It happens randomly, I could be going 35 on a flat surface, and try to accelerate and practically floor it to get to 40, almost 0 gain in RPMs.

I'm confused as to what caused all this. The only thing I can think of is that the ECU is flipped out due to the mass rpms (4-6) that were given to getting seafoam into the TB. (See opinions on seafoam thread for more info)

I'm going to try and reset this and hope it clears the problem. Blah, I feel routed...

 

just replace your belts altogether. Buy new wires if you havent already. At murrys auto parts, they got this bucket o cleaner that you hook up to your fuel rail. You then disable your fuel pump. You run this "stuff" until your car dies out (the can is gone) and its basically the same sh!t the mechanics do I -hear-. After that, maybe throw some heat in your tank, could have water maybe?

 

<div class='quotetop'>QUOTE (enigo @ Feb 18 2007, 08:38 AM) <{POST_SNAPBACK}></div><div class='quotemain'>Its not misfiring so much, but there is a definite failure to accelerate. Going up a hill I can floor it and still lose speed, the engine refuses to raise the its RPM above 2 - 2.5 Its nuts! Sometimes there is misfiring accompanying the problem, other times it just doesn't work. Its like my pushing the gas down doesn't do anything to the car.</div>


I've had the lack of power problem before, turned out to be plug wires that were broken down and shorting. Get yerself some NGKs or something



I also had the spluttering/misfire problem, where the revs go up to 3k rpm and then splutters down, over and over... and then would sometimes either just kick back in, or cut out the car completely. Also very random where you could be driving easy and when you try accelerate the pedal feels dead.

This one is still a mystery to me!
[My problem post]

I cleaned the air temperature sensor in the airbox, and the idle control unit with pure alcohol spray.
Problem persisted.
My friend drove my car very hard for 20 minutes, and the problem stopped for 2 weeks.
The car went in for a service, importantly the plugs & oil got changed. (i found my old Bosch yttrium plugs to give more power than the new ngk coppers)
Problem persisted.
I found that switching off the car and then starting again seemed to give temporary relief, also tapping the sensors under the hood.
Sent the car in to have error codes read, none whatsoever!
So after a 2000km trip I went and got myself a new MAP sensor, and since thats been on I havent had the problem again.... touch wood.



Oh, and so far as the skew chassis... you can get a good alignment shop to get her riding straight and stop eating your tyres... but your tight cornering will never be the same unless you have her pulled.

 

<div class='quotetop'>QUOTE (enigo @ Feb 16 2007, 12:45 AM) <{POST_SNAPBACK}></div><div class='quotemain'>I'm going to use the 2nd can of seafoam tomorrow and try to clear it out. Haven't figured out exactly where it all goes, but got a better idea. smile.gif (Thanks DrivingTibNaked)</div> You're welcome.

 

im thinking your mis-fire sounds alot more like a bad spark plug wire then anything else. id recommend replacing those next.

 

I'll have to check my TPS and MAF sensors, well mainly see if I got the gimp TPS.

I've pretty much deduced that the problem is related to the air/fuel ratio. I located the hole in the exhaust (the flex pipe is completely disconnected now) and the Oxygen sensor is right after the hole. I believe this is the cause of the problem, but I'm not completely sure.

It could possibly be the spark plug wires so I'll check those with an omh-meter. I tried to figure out which cylinder was misfiring, but each time I pulled a plug with the engine idling it got significantly worse. (Read up on how to do it here: General Info on Misfires)

I'm not sure how to fix the hole in the exhaust. Since its the flex pipe thats frayed all the way around, I suppose I could try welding something all around it. I looked at getting a header + flex pipe combo, but doing that pretty much slates me to put on a new cata and have to get a new exhaust pipes (would have to weld the new flex pipe to the stock pipes, since there aren't any bolt holes). Something I plan to do, just not when I'm broke as I am right now!

Thanks for the replies.

 

Well I talked to someone who knows more about cars than me (pretty much every other random guy on the street wink1.gif ) and based on how the car was acting, and considering what I had done to fix the problem, he thought it probably was the ECU.

Is that a likely possibility? Where could I get a replacement? Is there a simple test to check if the ECU is the problem or not? Since I'm replacing it, what are the possible upgrades besides just replacing it with another stock one?

Thanks!

 

well if you can find a nice 1.8 ecu out of a 98 elantra (only one i know for sure works is the 98), youll have your new ecu, AND and upgrade at that. Should only be 20-70 bucks, i got mine for 30 off ebay.

i dosent SOUND like an ECU problem 2 me, more likely either your MAF, or some other sensor....just me tho, others may know more and disagree

 

why would a 1.8 ecu be an upgrade? I figured a 2.0 ecu from a tiburon would be better, I'm confused.

 

Well the 1.8ecu will provide a bit leaner power map then the 2.0 will, I THINK. There have been a few threads that realy detail whats going on....try searching "1.8 ecu" that should get you to a thread i think REDZ started a while back that has all the pertinant info on it.

same sorta deal as adding the 1.8 cam to your motor, youd think it'd be the other eay around wouldnt you? lol.

but yeah, search it youll get much better info.

oh by the by, what kinda MAF sensor you got? (the brand, it says it on top the sensor housing). Ive heard one is kinda crappy, and one is good the Keifco is supposed to be the good one ive heard. Again im sure sombody else would know a bunch more then i do, hopefully youll get the exact awnser you need.