Skip to main content
Topic: Finally ROUGH IDLE may be cured!! (Read 4442 times) previous topic - next topic

Finally ROUGH IDLE may be cured!!

Reply #15
Quote from: thunderjet302;340474
Another thought but what did you do with the wiring when the swap was done? Did you change anything in the EEC harness? The SD HO swap does not require any harness repining. Also when you deleted the smog pump what did you do with the Thermactor TAB and TAD sensors?


Its my original harness. 

Hmmm.  I really don't remember what we did with the sensors when we deleted the smog pump.  Hell, they may just be unplugged.  Remind me where those even are...
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Finally ROUGH IDLE may be cured!!

Reply #16
Quote from: 50tbrd88;340507
Its my original harness. 

Hmmm.  I really don't remember what we did with the sensors when we deleted the smog pump.  Hell, they may just be unplugged.  Remind me where those even are...


On the passenger strut tower. I ended up looping the vac lines to them so there are no vac leaks. When I run a KOER test they throw a code but nothing else.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Finally ROUGH IDLE may be cured!!

Reply #17
Quote from: thunderjet302;340513
On the passenger strut tower. I ended up looping the vac lines to them so there are no vac leaks. When I run a KOER test they throw a code but nothing else.



Are you talking about these things?  As far as I can see they are all still hooked up.



Also, is it wrong to have this emissions block thing unplugged with my EGR and smog pump deleted?  I went ahead and took it out after I deleted the EGR but all the other vac lines have been unhooked since the HO swap. EDIT: (In hindsight, I guess since I had this unhooked, my EGR has had no vacuum to it this whole time).  Anyway, what exactly did those go to?  I am thinking one went to the intake, one to the EGR??  IIRC on the one that went to the intake, we plugged the port on the intake so there was no leak.




Maybe my problem lies with all this stuff.  I was thinking that since the line going to the intake was blocked off, the rubber emissions block was basically seperated from the engine and wasn't doing anthing anymore.
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Finally ROUGH IDLE may be cured!!

Reply #18
Quote
checked the 02 sensor wires and they look to be routed correctly. I really don't think these could have gotten swapped around on us, but I could be wrong.

Oh it's VERY easy to install them backwards/on the wrong bank.  Get a wiring diagram with color codes to double check as each side has different colors.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Finally ROUGH IDLE may be cured!!

Reply #19
Quote from: V8Demon;340642
Oh it's VERY easy to install them backwards/on the wrong bank.  Get a wiring diagram with color codes to double check as each side has different colors.



Yeah I was checking that last night and saw that they were different colored wires.  I will do a search online for a wiring diagram.

In the meantime I have been thinking about it, and what I have been overlooking is that there were symptoms of this problem before the HO conversion.  I keep looking into things that were changed during the conversion, but I think I need to look back further than that.

The most noticable problem before the HO swap was the surging at speed.  I thought the car needed a tuneup and maybe a new fuel pump and figured all would be well once the HO swap was done since those things would be swapped for new anyway.  I also remember the car running rough when you 1st started it (it even died a few times when I put it into gear), but with the stock exhaust and all the emissions equipment on, I didn't notice it "loping" like it does now or smelling rich.  I'm willing to bet it was doing the same thing then that it does now, maybe just not as bad/noticable.

I am now thinking this problem has been there all along and its just more noticable now with the loud exhaust and HO equipment.

There are quite a few things that could cause this that are original equipment.  The thing that keeps popping into my mind: distributor.  Its the original one with 180k plus miles so you know its probably worn.  How about TFI modules...what do they usually cause when they go bad?

Thoughts?
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Finally ROUGH IDLE may be cured!!

Reply #20
If the TFI or PIP are going they just die. No warning, nothing. They work on day and die the next.

I just thought of something that might cause this and explain why you can't pull codes: is your neutral safety switch hooked up? If not it will cause idle surging and the inability to pull codes as the computer won't know when the car is in park or neutral.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Finally ROUGH IDLE may be cured!!

Reply #21
Quote from: thunderjet302;340659
If the TFI or PIP are going they just die. No warning, nothing. They work on day and die the next.

I just thought of something that might cause this and explain why you can't pull codes: is your neutral safety switch hooked up? If not it will cause idle surging and the inability to pull codes as the computer won't know when the car is in park or neutral.


Not sure...actually I didn't even know there was a neutral safety switch on an automatic (lol).  I thought that was on manual's only.

I will check it out.  I assume its probably on the side or top of the trans?

On a side note, I just got home from work and checked the 02 sensor wires.  According to a schematic I printed off the internet the drivers side should have a blue wire while passenger side should have a green wire.  Guess what?  My drivers side has a green wire and my passenger side has a blue one.  We may have a winner here.  I will switch sides tomorrow after work and see what happens.  Keep your fingers crossed!
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Finally ROUGH IDLE may be cured!!

Reply #22
The o2 wire switch would be a problem.

Yes autos have a neutral switch. That way the computer won't start the car in drive or reverse ;)
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Finally ROUGH IDLE may be cured!!

Reply #23
Well we may have a winner.  Yesterday after work I pulled the 02 harness (which is a real beotch for a guy with big hands btw) and swapped it around.

Started the car up and it settled down into a real nice idle.  Took it for a quick spin and no miss under load.  I'm not gonna start jumping up and down yet, I want to put a few miles on it today and see how it acts.  But my nightmare MAY be over.

Thanks for the help guys!!
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Finally ROUGH IDLE may be cured!!

Reply #24
Whats the verdict???...........
88 sport,TW heads, comp xe270hr, cobra u/Tmoss ported lower, 65 mm throttle body, under drives,smog delete,
1.7 roller rockers, cai, k&n, bbk adj regulator, 76mm Pro-m,all MSD ign. MSD dist,18° base timing, 3g alt.1 5/8 ceramic headers, 255lph walbro, 2.5" h-pipe, flowmasters, silverfox valvebody, 3.73 gear,
http://i216.photobucket.com/albums/cc154/flipnbird/DSCF0185.jpg ( RIP : ( )

Finally ROUGH IDLE may be cured!!

Reply #25
02 wires were on the wrong sides.
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Finally ROUGH IDLE may be cured!!

Reply #26
Well now you can go on power tour:D

Can you pull codes now?
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Finally ROUGH IDLE may be cured!!

Reply #27
Quote from: thunderjet302;341197
Well now you can go on power tour:D

Can you pull codes now?

 
I have some other work to do before power tour.  Power steering pump has developed a bad leak, have a clunk in the front end I need to figure out (pretty sure its upper strut mounts), and the tranny is leaky as well.  I'm thinking about doing a front end rebuild in the spring as everything is factory original 180k mile stuff.

I need to check if it will throw codes now...I bought some electrical contact cleaner and plan to clean the 'plug in' (can't hurt).  I'm willing to bet it will throw codes now that the o2's are no longer crosseyed.
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube

Finally ROUGH IDLE may be cured!!

Reply #28
Thats great I bet your ecstatic!

Its always awesome when something has been fighting you FOREVER and you get it figured out. Wish I could have fixed it when my tranny was giving me hell.

Thinking I'm gonna have to do o2 sensors on my 96 soon. Every now and then I get a real rough idle on startup and occasionally comes up with lean codes on both banks. I've gone through all the usual fixes, hego's are the only thing left. Wouldn't surprise me, since their probably just as OEM as every other thing on this 190000 mile car....
--SteveN 👍
[thread=28690]1988 Cougar V6[/thread]
2012 F-150 3.7L

Finally ROUGH IDLE may be cured!!

Reply #29
Quote from: sarjxxx;341291
Thats great I bet your ecstatic!

Its always awesome when something has been fighting you FOREVER and you get it figured out. Wish I could have fixed it when my tranny was giving me hell.

Thinking I'm gonna have to do o2 sensors on my 96 soon. Every now and then I get a real rough idle on startup and occasionally comes up with lean codes on both banks. I've gone through all the usual fixes, hego's are the only thing left. Wouldn't surprise me, since their probably just as OEM as every other thing on this 190000 mile car....

 
Yeah, I was pretty much ready to "do a little dance, sing a little song (get down tonight)" when I realized it was finally fixed!!
'88 'bird, 10.9:1 306 w/TFS top end, forged rods/pistons, T-5 swap & bunch of other stuff, 1-family owned, had it since ‘98, 5.0tbrd88 on Instagram and YouTube