sirrobert09 Posted April 13, 2014 Author Share Posted April 13, 2014 I have not replaced the knock sensor nor did anything visually look wrong but it could still be cracked on the side i cannot see my experience my 98 impreza threw a code when the sensor cracked. If it was leaning out causing it to pull timing it would still be fuel related not the knock sensor tho? Link to comment Share on other sites More sharing options...
sirrobert09 Posted April 13, 2014 Author Share Posted April 13, 2014 i have 2 charts i logged while fussing with it they are taken at separate times in the first one Air to fuel ration measured 15 seconds to 29 seconds is with light throttle the other segments are when I give it normal throttle in the stuttering range http://i1159.photobucket.com/albums/p633/alestor666/screenshot_zpsc8e5ebc9.jpg?t=1397426414 the second one is the timing advance at the start is with blipped throttle when it stutters then it flat lines after letting off the second major dip is at about 23 seconds with a small bit of throttle timing was pulled to almost -15 this isn't normal is it? http://i1159.photobucket.com/albums/p633/alestor666/screenshot1_zpsb113c137.jpg?t=1397426412 i didn't want to post the images in the post as they where huge Link to comment Share on other sites More sharing options...
Cougar Posted April 17, 2014 Share Posted April 17, 2014 I am wondering about the MAP sensor. I suspect it may be causing the issue. I also wonder if the TPS sensor might have a problem when the throttle is moved quickly so an incorrect voltage is getting to the ECU for the position it is at. That is kind of a long shot possibly. Link to comment Share on other sites More sharing options...
sirrobert09 Posted April 19, 2014 Author Share Posted April 19, 2014 well when the car first wouldn't start and the key was in the run position there was a short electrical wine coming from somewhere in the engine bay. After replacing the fuel pump it never cam back so i just dismissed it. any good ideas on checking the voltage versus what it should be? Link to comment Share on other sites More sharing options...
sirrobert09 Posted April 20, 2014 Author Share Posted April 20, 2014 for amusements sake i unplugged the knock sensor just to make sure it wasn't causing any issues the timing advance looked slightly less erratic for a second then right back to normal with the same results under throttle. I have no idea how far the throttle should be open at idle the computer says its idling at 14% throttle and seems to be responding on the graph correctly. What are the two black objects inline near the firewall one on the fuel line in and one on the return line they are about where the fuel filter would be on my 98 rs and 03 wrx. Link to comment Share on other sites More sharing options...
Cougar Posted April 21, 2014 Share Posted April 21, 2014 I'm not sure what the inline devices are but if I have to guess they may be one way valves to prevent fuel back flow. Link to comment Share on other sites More sharing options...
willwright Posted April 22, 2014 Share Posted April 22, 2014 Well this is sounding exactly what my 03 is starting to do except I have no codes. Same engine with 5 speed manual tranny. If I figure it out before you do I will post what I found here. Good luck to both of us, we will figure it out. I am dedicating the next 3 days solid working on it. Link to comment Share on other sites More sharing options...
sirrobert09 Posted April 22, 2014 Author Share Posted April 22, 2014 Well this is sounding exactly what my 03 is starting to do except I have no codes. Same engine with 5 speed manual tranny. If I figure it out before you do I will post what I found here. Good luck to both of us, we will figure it out. I am dedicating the next 3 days solid working on it. Oh no I have no engine codes any more those codes where gone with the new fuel pump now its these symptoms with no codes. if you find out please share. I started pulling the cats before work but ran out of time I suspect mine are clogged. Link to comment Share on other sites More sharing options...
willwright Posted April 22, 2014 Share Posted April 22, 2014 I found the problem , my plugs were down as far as they would go, however, my number 3 wire was not ( snapped onto then plug itself. The spark was jumping / arcing against the head basically hit and miss . Under a load it was sputtering and all that jazz but not under a load above 2200 rpm it was fine. I beat my head against the wall 2 days to figure this out. If u do not hear that snap when it goes on finally, then its NOT on and causes this to happen. Link to comment Share on other sites More sharing options...
willwright Posted April 22, 2014 Share Posted April 22, 2014 I meant plug wires were down as far as they would go, it basically was getting some fire which made it idle fine and above 2200 rpm it was fine, no codes no misfire nothing, but under a load at low rpm it was bucking slightly is only way I know how to describe it. Sounds absolutely identical to your issue, push them until you physically hear them snap onto the plug. If they don't then they aren't on there. I am going to watch your post and man I hope yours is that simple. I am a very decent wrench and no one would have convinced me those wires weren't on right. Link to comment Share on other sites More sharing options...
sirrobert09 Posted April 23, 2014 Author Share Posted April 23, 2014 I had checked the wires already reading about them not being clicked in. So i did double check them to be sure they are all clicked in just replaced them during this problem. Haven't been able to get back into it since its been wet and cold these last few days and I'm working outside Link to comment Share on other sites More sharing options...
sirrobert09 Posted April 27, 2014 Author Share Posted April 27, 2014 (edited) okay finally a success after building a fuel pressure tester ( fuel pressure came out good) pulling the cats (not clogged) finally just pulled all the injectors and built myself a cleaning rig. set the psi on my compressor to about 20 ran straight chevron techron through them both directions back in the car no more stuttering. Car still feels kinda lacking on power tho but may just be from me going from my wrx to automatic 2.5i Thanks for all the help Edited April 27, 2014 by sirrobert09 Link to comment Share on other sites More sharing options...
willwright Posted April 27, 2014 Share Posted April 27, 2014 Very glad to hear you got it figured out. Link to comment Share on other sites More sharing options...
sirrobert09 Posted May 1, 2014 Author Share Posted May 1, 2014 well all figured out but i cant get the injectors to seal back up in the manifold they leak from the top on the passenger side the driver side is just dripping. They where fine with no leaks after installation. the o-rings are not torn and the bolts are all the way down. Was going to try another set of o-rings from my metric box that are a tiny bit thicker. Would they hold up to the fuel or do they need to be made of something special? Link to comment Share on other sites More sharing options...
willwright Posted May 1, 2014 Share Posted May 1, 2014 O rings are o rings if they fit, nothing special about them. Always best to replace them any time you pull injector out. You can use some petroleum jelly to help them slide INA bit easier. Link to comment Share on other sites More sharing options...
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