1999 3.8 runs rough not 100% 😩 - Mustang Evolution

Go Back   Mustang Evolution > 4 Cylinder | V6 | Classic Mustangs || Tech and Talk > Pre-2005 V6 Mustang



Reply
 
Thread Tools Search this Thread
Please support our sponsors and let them know you heard about them here!
Old 07-16-2016, 10:47 AM   #1
Registered User
Newbie
 
Join Date: Jul 2016
Location: Queen Creek
Region: Arizona
Posts: 9
1999 3.8 runs rough not 100% 😩

K so I picked this car up on a trade for my sierra p/u. When I got it I knew it needed a clutch an maybe a few other little things. So I ordered an installed the clutch, while in there I did the rear main seal both motor mounts an trans mount. Just for the hell of the car being new to me I did new oil an fuel filters, plugs, valve cover gaskets for a small leak, obviously new upper intake gasket, an while I was that far I had the injectors cleaned an tested. Also while doing this I did find out about the stupid key chip cause the theft light would flash before so I fixed by duke tapping a ke to it under the trim so now that light is off an also the check engine light works but no light an also no codes with my little autozone scanner.

My question is after all of that the car still sounds an feels like it has a dead miss. WTF My next time I get to work on it sold be in a few hrs an I'm going to check the fuel pressure an cyclider compression. If this are good I might light it on fire πŸ˜­πŸ˜–
DaQNYAZ is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 07-18-2016, 06:34 AM   #2
Registered Member
Regular
 
yogibooboorange's Avatar
 
Join Date: Jun 2015
Location: LaPorte
Region: Indiana
Posts: 65
Was there a miss before you changed plugs? You may have inadvertently messed up one of the spark plug wires, while pulling off the plug or something else. If it had a miss before your work, then it could ne any number of things.
yogibooboorange is offline   Reply With Quote
Old 07-18-2016, 11:55 AM   #3
Registered User
Newbie
 
Join Date: Jul 2016
Location: Queen Creek
Region: Arizona
Posts: 9
Yes it had the issue when I got it. Has gotten better after all the work but no were close to being like it should. Last night late I checked fuel pressure. KOEO 40psi, idle 40psi, an 1500/1800 rpm's 50 to 55. I also checked the maf an the plug with a better dvom an it's the best one I've ever seen. I didn't check the compression yet but did take temperature of each exhaust down tube an it seems as if #4 is the coolest on idle @170Β°f while the other 5 are 50 to 80 hotter? I sure hope the failure isn't in the valves
DaQNYAZ is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 07-18-2016, 01:25 PM   #4
Registered Member
Regular
 
Jbone007's Avatar
 
Join Date: Mar 2015
Location: Oceanside
Region: California
Posts: 435
Did you change the wires out also when you changed the Plugs? It does sounds like you are on the right path in troubleshooting with the lower temperature on # 4 Cylinder. I would think that it would be throwing a Check Engine light/code if it is that noticeable but never know on these older cars.
Jbone007 is offline   Reply With Quote
Old 07-18-2016, 01:44 PM   #5
Registered User
Newbie
 
Join Date: Jul 2016
Location: Queen Creek
Region: Arizona
Posts: 9
Funny thing is the car had a maf code when I got it but the light never was on? I cleared it an cleaned it. As I said the maf sensor is almost scary it's so firm on its voltage. I mean the best I've ever seen.
Yes the wires are new, maybe I should pull em an hit them with the meter
DaQNYAZ is offline   Reply With Quote
Old 07-18-2016, 02:02 PM   #6
Registered Member
Regular
 
Jbone007's Avatar
 
Join Date: Mar 2015
Location: Oceanside
Region: California
Posts: 435
Yep can never tell on the wires may have got a bad one. My co-worker had 14 codes on his BMW and replacing the Maf resolved them all lol!
Jbone007 is offline   Reply With Quote
Old 07-18-2016, 08:36 PM   #7
Registered User
Newbie
 
Join Date: Jul 2016
Location: Queen Creek
Region: Arizona
Posts: 9
Ok, just did 12hrs @ work an really didn't want ta come home to this but I will say when ya upset an ya just dig in an bang it out. Doin the compression test wasn't the pain I thought. So, every cylinder was over 155 #2 & #6 was 170
Did the wires also an they are good. Where to know? I'm thinking EGR but at the same time I feel like that can't be it unless it was stuck wide open? Gonna pull it any way, hold please lol
DaQNYAZ is offline   Reply With Quote
Old 07-18-2016, 08:44 PM   #8
Registered User
Newbie
 
Join Date: Jul 2016
Location: Queen Creek
Region: Arizona
Posts: 9
Nope, not the EGR. It even looks like it's been changed so I'm thinking the old owner knew he was getting rid of a headache
DaQNYAZ is offline   Reply With Quote
Old 07-19-2016, 10:46 PM   #9
Registered User
Newbie
 
Join Date: Jul 2016
Location: Queen Creek
Region: Arizona
Posts: 9
Ok Ok I think I might have something...
So I got off early today an wasn't gonna take no (not knowing why it runs like poop) for an answer. I'm just gonna say, going back to basics is always a good thing. Turns out the coil isn't firing the 1st bank. I do believe I read somewhere that 1 & 5 fire at the same time then 2 & 6 then 3 & 5? Anyone can tell me how I'm testing this failure, I thought also this fix was to change out a ecu? Would definitely want to know that's what it is before I spend the cash on one. Also right before I was gonna do a test fire I'm hooking th battery up an there was a lot of clicking unerring the R/f fender well? Da **** that's about?
DaQNYAZ is offline   Reply With Quote
Old 07-26-2016, 02:06 AM   #10
Registered Member
Regular
 
Join Date: Jul 2015
Location: stafford
Region: Connecticut
Posts: 99
My car was giving me the same type of issue. When I checked the fuel pressure it looked good, but if you snapped the throttle open fast the pressure would drop to 20 or so and come back up. The car would pop and sputter going down the road at half 3/4 throttle. The issue was the fuel pump controller in the trunk. It tells the pump how fast to spin to make pressure.
dcarr is offline   Reply With Quote
Old 07-26-2016, 03:26 PM   #11
Registered User
Newbie
 
Join Date: Jul 2016
Location: Queen Creek
Region: Arizona
Posts: 9
Found the F-ing issue. Was the plug wire. Good call Jbone007 cold air an full exhaust is next. Then hopefully before xma's I'll do the cam heads injectors an mapping 😈
DaQNYAZ is offline   Reply With Quote
Old 07-26-2016, 03:29 PM   #12
Registered Member
Regular
 
Jbone007's Avatar
 
Join Date: Mar 2015
Location: Oceanside
Region: California
Posts: 435
Glad it was a simple as that!
Jbone007 is offline   Reply With Quote
Old 07-26-2016, 03:33 PM   #13
Registered User
Newbie
 
Join Date: Jul 2016
Location: Queen Creek
Region: Arizona
Posts: 9
I wish it was. I dam near rebuilt by replacing the hole dam car lmao can't stress enough how we have to go back to basics lol man I thought the wires were good.
DaQNYAZ is offline   Reply With Quote
Old 07-26-2016, 03:42 PM   #14
Registered Member
Regular
 
Jbone007's Avatar
 
Join Date: Mar 2015
Location: Oceanside
Region: California
Posts: 435
Yep always seems to be what we least expect!
Jbone007 is offline   Reply With Quote
Old 07-31-2016, 04:13 PM   #15
Registered User
Newbie
 
Join Date: Jul 2016
Location: Queen Creek
Region: Arizona
Posts: 9
I got a battery light now. Put like 500miles on the car an it cam on an went off 3 times an now it's still on. Battery load tests good an alternator is putting out 13.98 I've changed the batt terminal, an checked the connection on alt an fuse botx. Any suggestions on anyother faulty wire or plug?
DaQNYAZ is offline   Reply With Quote
Old 07-31-2016, 04:29 PM   #16
Registered Member
Regular
 
Join Date: Jul 2015
Location: stafford
Region: Connecticut
Posts: 99
Check the grounds on the radiator support
dcarr is offline   Reply With Quote
Reply

Lower Navigation
Go Back   Mustang Evolution > 4 Cylinder | V6 | Classic Mustangs || Tech and Talk > Pre-2005 V6 Mustang

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Mustang GT RUNS ROUGH AFTER TUNE GT Lover 2005-2010 Mustang GT 22 11-08-2014 05:19 PM
Car runs rough Liebert91stang General Mustang Discussion 5 08-16-2013 04:00 PM
Disconnected Battery now runs rough bradh2414 1996-2004 Mustang GT 9 08-01-2013 08:40 PM
02 GT runs rough with AC on Ckennedy121 1996-2004 Mustang GT 10 05-07-2013 09:10 AM
>>>>1965 mustang 289<< help!!! runs rough!!? bao Classic Mustangs 1 08-24-2009 03:22 AM

» Like Us On Facebook



02:06 PM


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0

MustangEvolution.com is in no way associated with or endorsed by Ford Motor Company.