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rough idle and knock!

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geno414

10+ Year Contributor
440
4
Jan 13, 2011
Milwaukee, Wisconsin
Came home from work fixed a alternator belt and put some (stp red bottle) in my car .

The car starts up a bit rough and i will have to keep my foot on the gas wile it warms up . When it is warm it sounds like I have some big big cams in my car witch I don't . My a/f bounce around a bit two but most of the time it will be around 14 . My idle will bounce a little bit from 1000 to 500 when I start breaking it will die some times I don't know what is the problem it just randomly came and when building boost I will get a check engine light for knock witch I never ever get it is protune on dsmlink.

I have a 6 bolt swap done the right way support mods the works .

I replaced the plugs to see if that was it but didn't make a difference . Swapped coil pack nope nothing did some sea foam to my car to see if that stp messed it up nothing.

I tested all injectors checked for lose wire or anything looked for boost leaks found one fixed it still did not fix my car . The car runs good on the high way besides when I build boost and get a code for knock and then the hole idle thing. My timing was set right and was done right my base time on dsmlink is 5* o2 is cycling like it should nothing adds up really I am stump PLEASE if any one has had a problem like mine can you help and yes I have looked on the Internet for a answer already
 
Since no one else has mentioned it yet, perform a boost leak test. Warm water and soap are a big help to find those pesky leaks. Pay special attention to any couplers, throttle body, and fuel injector seals. Being so cold, leaks can form.

You can check the knock sensor to see if the portion the harness comes out of looks like it is leaking/melted. If so, it needs replaced.

The wideband is working properly if it is bouncing around at idle and cruise speeds. That is your ecu compensating to reach a target AFR of 14.7. It should average about 14.7, but may bounce between 14-15.1

Feel free to post a log as well.
 
Take off your knock sensor.and.inspect it could.be phantom knock unless you acually.hear.it knocking and no.forsure

If you actually hear knock during a WOT pull, it's most likely too late.

I had a boost leak and I fixed it

Did you keep testing and fixing them until you can hold 5psi above max boost? I can't recall ever seeing a car in average condition with just one boost leak.

*****

Follow this, and then post a log in the tuning help forums.
 
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My boost leak test I made does not hold the boost very well it works and all I know is I fixed the boost leak LOL and no I can not hear a knock when wot or driving I stopped driving it since this happened and since then I have been doing nothing but looking up symptoms of stuff I know my timing is set right dsm link says it's at 5* before I start it and I timed it right and that was last year I looked up gofers 1 2 3 tooth off and how the results would be and I don't have any of them to be honest the car idles like I have 272 272 cams in the car really rough and choppy when driving it's normal until I hit 10 psi my engine light will flash and that's where my knock is set at to turn on to notify me that I have knock I don't know I just need it fixed
 
CHeck your idel air control screw make sure it is sealing
 
Since no one else has mentioned it yet, perform a boost leak test. Warm water and soap are a big help to find those pesky leaks. Pay special attention to any couplers, throttle body, and fuel injector seals. Being so cold, leaks can form.

You can check the knock sensor to see if the portion the harness comes out of looks like it is leaking/melted. If so, it needs replaced.

The wideband is working properly if it is bouncing around at idle and cruise speeds. That is your ecu compensating to reach a target AFR of 14.7. It should average about 14.7, but may bounce between 14-15.1

Feel free to post a log as well.

You have still not posted a log.........
You also still have boost leaks..........
 
A vacuum leak will make it run rough, so will a bunch of other things like a stuck open egr valve. Have you checked ignition timing, and did you swap the power transistors when you did the coil pack?
 
I do not have boost leaks I said in the other post I had a boost leak I fixed that boost leak no one has asked me to post a log so on that note would you like a log wile he car is cold or fully warm . I can get a log tonight up I am at work right now at the moment.
 
Yea I have two working power
A vacuum leak will make it run rough, so will a bunch of other things like a stuck open egr valve. Have you checked ignition timing, and did you swap the power transistors when you did the coil pack?
I have to working power transistor 2 working coil packs 2 sets of plugs wires egr delete no leak no fuel leaks or o ring leaks my ignition time is set at 5* and timed right this weekend I want to check to see if timing jumped at all but I doubt it did all I did in the past when it worked to now is just put on a alternator belt and a red bottle of stp and I'm left with this a car run in like crap .
 
There's no point in guessing anymore, we need to see a log of the event. You've covered most of the basics, but without being able to see in person it's hard to tell.
 
I do not have boost leaks I said in the other post I had a boost leak I fixed that boost leak no one has asked me to post a log so on that note would you like a log wile he car is cold or fully warm .

I referred to posting a log in both of my posts. My first post was the 2nd one in this thread. I would post both logs. Also a cruise log wouldn't hurt either (car warmed up of course).
 
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this is a video I have on my phone of the car I will be going home to make a log in just a jiffy I just wanted to tank every one for helping me so far and taking time out of your day . For me.
 
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this is a slight warm idle and a cruz with some boost gears reverse 1st 2nd ( snow on ground and some knock)

car is a 2.3L ignition set at -5 till 1500 rpm then it is +1 on time never had a problem with this tune ever

my car has sat for 4 or more days now and I could start the car good and didn't have to hold the gas peddle like before it seems like it is running a little bit better but not much .
 

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  • log.2015.02.09-01.elg rough idle 2g with knock..elg
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Does anyone know what I gotta do to open log files on my android? I download the file but cannot open.
 
how about your injector deadtimes on link?
660 cc set to 180 and off the top of my head I think global is around -30 or something I'm st work tho ik my ingectors r set up right tho the car has a protune on it I started it up and it seems to run a little bit better don't know why tho
 
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