Ok so here is the issue and wondering if I can do a quick fix before getting the car dyno tuned next Thrusday.

Quick overview. Installed PFTB and Idles around 850rpm and no surging issues. Using DE-K TPS and IACV in PF housing (no coolant bypass). Car runs fine pretty much. Ran a multimeter and TPS is pretty close at 4.3.

Over the weekend I installed NWP Manifold spacers and hooked everything back up. Now the car runs poorly at idle and cold start. Car shoots up to 3000 rpm at start up then drops to 1200-1500rpm. Once car is warmed up it sticks around 1000-1200rpm. Idle is very rough and AFR is around 16/17 at idle. More into the 18’s while cold.

While driving the car, it runs very smooth and AFR is where it should be around 14.5-14.7 nothing higher.

So overall the main concern is idle at stop or when in park (car is auto). Is this still a TPS issue? Doesn’t seem to be tuning related since it is at idle. I’ve done some reading on TPS and pretty sure I got it right. 4.3 is very slightly off from what the Max should be set at, or does such a slight difference cause such a huge issue? I would like to figure this out on my own before going for a dyno tune.

Thanks,

 

Check vacuum lines, you have a 2000 so there are a lot of them, you may have missed one and its causing driveability issues.

 

Air leak, which is causing the lean issue.

Places to check would be PCV lines, then perhaps if those are fine, maybe some minor air leaking into the IM from the spacer/IM interface.

 

Did you use RTV for the spacer install?

 

What's weird is the high idle ... that's an interesting one there. High idle & lean =

When mine idles lean it just about shuts off (idle lower than usual)

 

Vacuum leaks can cause high idle on other cars.

 

Thanks, got a friend coming by today with his max to cross reference the lines. I used high heat RTV on the spacers. Funny thing is the factory gaskets had now sealant originally :S

 

Sounds good. PS I posted in your last PFTB thread, regarding the 3" MAF housing setup, let me know what you think.

 

I saw that, gotta try it on the weekend as I will wake the neighbors up by the time I get home lol.

Also during the install made a slight oversight which would happen over an 8 hour install. Started the car and almost flipped out! Forgot to hook up the brake booster back! Lesson learned on that lol

 

also check that the throttle cable isnt being tugged slightly cuz of the tb spacer. never seen it happen but u never know

 

Friend couldnt make it today. As for the throttle cable, i dont see that being the issue as the 5th gen cable is very long! Wraps around the vi

 

very true, but it can still be tightend too much however.

 

Sounds like what my car did when I unplugged the tps.

 

Also make sure your IACV is plugged in all the way.

 

It was too late to start the car up to test, but Im confident I found the issue.

First issue is the rear fuel rail vacuum line. It was hooked up wrong. Should go to a small vacuum feed sitting below where the front rail vacuum connects. So that was an open vacuum to start.

Second is the throttle cable. Since the 5.0 gen throttle cable goes around the manifold, it has an angle that no longer lines up straight the the PFTB. When opening, the cable gets slightly hooked temporarily when releasing the gas. I will need to make bracket to line up the cable better.

BTW IACV is fine as there were no issue before the spacer install. I did double check and its fine. (DEk IACV sensor in the PF housing)
I didnt get to start it up, but Im positive these 2 things are causing my issue. Once the rain stops and I make a bracket, I will confirm for those with a 5.0 gen looking to do similar TB mods.

 

Good find^

We had a similar idle problem with a 3.5 swapped 4th gen down here. It turns out a mistake was made while assembling the converted E-throttle body. It would cause the TB to stick partially open after the throttle was pressed. We fixed that but decided to go with the PF TB and then had a problem with the TB not opening 100%. This time it was just hitting against a little vacum outlet on the IM acting like a stoper limiting the throttle to about 80%. We just bent that out the way and problem now solved.

Its not related, but shows how easily we can miss "obvious" little mishaps.

 

Hopefully it works out as I have dyno time booked next week for tuning

 

So I was finally able to check things out with the car running. The major leak is coming fron the TB spacer and manifold. Will need to replace that gasket with those thicker spongier ones

 

Gasket fixed now and throttle cable fixed. Car is running well but clearly needs a tune now which I hope happens next Thursday

 

WOOOWOOOOOOOOOO

 

Lol you sound more excited then me lol. Dynomay not happen next week due to work scheduling, but will happen by the end of this month/early July the latest

 

I'm about to have a cammed DEK too

 

Now that your UIM is ported for that pathy, all you gotta do is polish those headlamps for aerodynamics, throw on the BBmaf and this motor should finally get to see some 12's again

Glad it worked out, dandy's ol gasket just wouldnt scrape off the TB bolts and that OEM gasket didn't have enough girth, we should've thrown some gorilla tape in there from the getgo.

 

Nice...

By the way, JB stick works awsome for TB leaks...



Ask me how I know....

 

Very highly doubt this will see 12's again. Too heavy and Im still auto, plus Dan had the cut out. Only thing I have he didnt was the spacers.

 

Just an update that the car is running amazing still, noticed the exhaust is quieter also, but clearly needs tuning now (14.9 at idle/cruise and low 10's at almost WOT and didnt want to push further)

Scheduled for next Thursday to get it fully dyno tuned and see what it puts down tuned! In 08 I dyno'd at 200whp with a basic street tune, bad 02, OEM cat, no PF TB, no NWP spacers, stock muffler with Budget b-pipe. Any guesses? Also the BBMAF will be in with a brand new MAF sensor, velocity stack and oversize AEM dry flow. Fingers crossed lol

 

I say you make 220whp and 210wtq because you're auto. (if i recall) But I want you to prove me wrong and make more. lol.

Ever thought of doing a 5 speed swap?

 

Dyno, TDot?. I thought you put down 200/180? whaa when where 220??

 

lol. Nah man! Im GUESSING he'll make that much. lol

 

5 speed is in the works, grabbed some parts but the car needs a paint job so Im focusing on that first, so wont be for awhile. 220 is a good guess, I hope you're wrong also. Nmex you're right 200/183 originally

 

sloppy was close to what you did w/o a tune, so I'm sure you should be well above 220. Ahh man, not staying AT,

I suppose the dynamics of your situation would prove that MT would be the best option though, (DEK, a lil less tq, more weight than an A32)

 

Yes no auto in 2 years maybe? When I got this car I was supposed to onlylower it and got auto due to my commute (previous cars all manual). But I have a 10 minute drive now so its annoying to me not having manual. Espiacially now with the vb mod and pf tb etc, I can feel the auto struggling to keep up.

 

Vacuum leak..

 

Good choice. For an N/A dek in a 5th gen chassis its a must in my book. I went from an embarassing 16.1 second run at the track to a 14.8 with a bad launch and the only changes were the 5 speed and headers. Headers alone will not drop an entire second off the ET. lol

 

Headers are fairly significant as well.


Damn you sloppmax!

 

Well life sucks lol. Another last minute project and launch I need to work on so Im no longer off Thursday to get this done. Delayed again. Not sure when I'll get the time, but I'll be sure to post results once done. In the meantime Im going to try different settings (z32, rb26 etc) to see if I can get the BBMAF going at least.

BTW anyone have the link to sloppymax dyno thats similar? I can only find his 175hp run and his 5.5 gen run.

Thanks,

 

I have his runfiles, just not here. They're at home.

 

Project now cancelled to many small issues getting in the way including the major which is painting the car and it being auto. I am going to be restoring the car to stock form and looking for a 6-speed 5.5 gen to dump whatever parts I can into it. Hopefully the car gets sold to someone who will put this motor back to its full potential.

Next summer be on the look out for a new 5.5 genner around