misterp Posted March 4, 2007 Report Share Posted March 4, 2007 Hi all - the good news is that I have my tranny back in the SS (with help - thanks gents!); bad news is that the engine runs very very rough, stumbling at 500RPM and hunting for idle, running rich too right from the instant it starts. I babied the throttle for about 60-seconds to verify there were no leaks and run the shifter between P/R/D then shut it down. I'm stumped - I'm thinking that I've failed to plug something back together correctly but what? The SES light is not lit so no codes. I've been all over the truck these last couple days so I guess it could almost be anything, is there a good way to troubleshoot this kind of problem? How can I tell if it's O2 sensor or maybe I bumped the MAF connection crawling atop the engine or ??? Mr. P. Quote Link to comment Share on other sites More sharing options...
desrtrat Posted March 4, 2007 Report Share Posted March 4, 2007 i'm not the sharpest tool on this, but check ALL your grounds, maybe good luck Quote Link to comment Share on other sites More sharing options...
PladdPezzPunk Posted March 4, 2007 Report Share Posted March 4, 2007 If the battery was disconnected, you may have to drive the truck for a period of time for the fuel trims to relearn. Keep in mind when disconnecting the battery, the throttle will have to re learn also (and all adaptives for that matter). also i would clean the mass airflow sensor with CRC MAF cleaner to make sure there is no problems there. good idea when ever replacing the tranny cause it it the primary part that will adjust line pressures and command the pressure modulator in the tranny. Also, the front o2 sensors can do similar things to what you are describing. I know the one on the passanger side is a bit of a MF to reconnect and put in the factory position. If all else fails, run a log and send it to me. i could probably tell from that. Let me know. Hope this helps. Quote Link to comment Share on other sites More sharing options...
misterp Posted March 4, 2007 Author Report Share Posted March 4, 2007 (edited) Ok that's a starting point. MAF was cleaned 3 weeks ago with Radio Shack electronics cleaner and I did not undo it so I doubt it is dirty. Yes battery was disconnected for a week, but I've done that before and never had this kind of issue??? Also, IMO it's running way worse than just relearning fuel trims but that's just an impression; it idles/runs so bad as to not be driveable, it had to drive with two feet to make it move fwd & back a couple yards. Warming the engine does not improve things. Never disconnected pass side exhaust or O2s; I did remove the driver's mid-pipe but the O2 connectors snapped right back into place and I even installed the blue safety clip, maybe they need to be undone/redone? The thing that stumps me is that there are no codes. I did have a fight with both the starter & dip stick tube (god damned thing) the dip stick was hanging on a small wire attached to the rear of the pass head (ground wire?) but it still felt good after we got the dipstick installed. I did throw a quilt atop the engine and laid on it to undo the top bellhousing bolt from topside; maybe I upset something on the intake? Tomorrow I will take a flashlight and make sure a wire didn't get pinched between the bellhousing & block but I highly doubt it. Mr. P. PS - did not know that about MAF & tranny line pressure... Edited March 4, 2007 by misterp (see edit history) Quote Link to comment Share on other sites More sharing options...
Bowtie70SS Posted March 4, 2007 Report Share Posted March 4, 2007 You have logging/scanning software don't you? If nothing obvious shows up then hook up to it and watch your engine parameters. Maybe you will see something that will shaed some light on your problem. There are a couple of ground wires on one of the upper bellhousing bolts if I remember correctly. Dave Quote Link to comment Share on other sites More sharing options...
perk03z06 Posted March 4, 2007 Report Share Posted March 4, 2007 Just because check engine light isn't on doesn't mean there's no codes. You might have codes waiting in pending for other criteria before becoming "hard" codes that actually turn on the light. Quote Link to comment Share on other sites More sharing options...
04CHASE Posted March 4, 2007 Report Share Posted March 4, 2007 well it could be so many thing and its hard to say wihtout having the truck here. but as perkz said it could have immature codes. mr p you need to get some kind of scanning tool. is it making any weird noises? or just running like crap? does it feel as if their could be a misifire? i doubt you knock a plug wire loose , a code would get set pretty quick. Quote Link to comment Share on other sites More sharing options...
Krambo Posted March 4, 2007 Report Share Posted March 4, 2007 I would get her to temperature so that you exceed the adaptive idle parameters (set-point temp) and see what happens. You have a 160 in there correct? Did your tuner ever drop the minimum "learn" temp in that cell to like 150 or so? Otherwise you may never get to the set-point. Keep us posted... Quote Link to comment Share on other sites More sharing options...
misterp Posted March 4, 2007 Author Report Share Posted March 4, 2007 Thanks for the hints, I went out this morning and just let the truck run until it went Closed Loop and *bingo* it smoothed right out so I guess that Pladd was right it needed to adapt. Took the truck on a 15-min highway drive and that helped it as well, now it runs well enough to get me around but it's still not running right, part throttle is kinda shaky and it does hunt for idle pulling up to a stop light, parked the idle stumbles at least once a second I did capture a little over 1-minute of ODB2 scan data in a CSV file that can be looked at in a spreadsheet program (the truck was idling); I've got really no idea what I'm looking for other than the O2 & spark readings are all over the place but I've got no idea if that's normal behavior at idle. Warm Idle scan log Mr. P. Quote Link to comment Share on other sites More sharing options...
kelleyperformance Posted March 4, 2007 Report Share Posted March 4, 2007 (edited) damn it must be cold outside its normal for the spark to jump arround at idle. thats just the adaptive idle control doing its best to keep the commanded RPM. the O2 readings will also look like they are small children on crack doing jumping jacks. i did notice that your LTFTs are horrible. go drive it arround at operating temps some more, you need to fix those. everything looks normal to me steve, other than the truck still learning the fuel trims..... put like at least 50 miles on it and then see how its running. Edited March 4, 2007 by kelleyperformance (see edit history) Quote Link to comment Share on other sites More sharing options...
misterp Posted March 4, 2007 Author Report Share Posted March 4, 2007 (edited) Thanks for looking at the data - those LTFTs were after 25-minutes of driving. OK I have some codes, finally happened while I was driving around town running errands: P0101 Mass Air Flow Circuit Range/Performance Problem (twice) P0171 System Too Lean Bank 1 P0174 System Too Lean Bank 2 Do I have a vacuum leak? Edited March 4, 2007 by misterp (see edit history) Quote Link to comment Share on other sites More sharing options...
foxySS Posted March 4, 2007 Report Share Posted March 4, 2007 I was gonna say possibly an ignition wire not connected? After seeing those codes, not too sure about that now though. When I removed most of my whipple craptronics there was some sort of ignition wire that had to be connected that I missed and it stumbled and idled horrible! It was blowing tons of black smoke out the tailpipe and struggling to stay running. Just a thought. Quote Link to comment Share on other sites More sharing options...
gixxerrider Posted March 5, 2007 Report Share Posted March 5, 2007 Bad ground? Quote Link to comment Share on other sites More sharing options...
04CHASE Posted March 5, 2007 Report Share Posted March 5, 2007 could be a vacuum leak. are you familiar with the break cleaner trick? Quote Link to comment Share on other sites More sharing options...
misterp Posted March 5, 2007 Author Report Share Posted March 5, 2007 could be a vacuum leak. are you familiar with the break cleaner trick? Total rookie move The CAI intake tube was leaking at both the MAF end and the throttle body end; when raising/lowering the engine from under the truck the CAI moved enough to pop itself out of it's seals. I used starting fluid to find the leaks and verify that the intake itself & all hoses were also leak free, the idle is back to normal, no surging anymore and the idle LTFTs are now at zero. Thanks to everyone for their suggestions Mr. P. Quote Link to comment Share on other sites More sharing options...
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