2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

Car runs again, but with new hesitation problems

Thread Tools
 
Search this Thread
 
Old Jul 8, 2004 | 11:58 PM
  #1  
gsracer's Avatar
Thread Starter
EIT
Tenured Member 10 Years
 
Joined: Jan 2002
Posts: 1,790
Likes: 0
From: Austin, TX
Unhappy Car runs again, but with new hesitation problems

Well it's been a while but my car runs. I blew up the stock turbo at the dragstrip back in mid january, and came back home on the weekends to work on it. I've since added:


4 x 720cc fuel injectors
greddy e-manage - with injector/ignition/pressure sensor harness
RB turboback (had tf dp/mp with a n1 before)
BNR stage II
HKS BOV
pulled engine harness apart, followed the wires that were involved with emissions back to the ecu and pulled their pins, then completely re wrapped the harness.
rats nest and related emission equipment removed
TB Mod
PLX - M300

The ugly:

TPS sensor is completely busted. With the plunger at full travel, the TPS had ohm readings into the 20k plus category. I disconnected the TPS, and have already purchased another one in good shape; however it's not here yet. I put the IC back on and tried to make a few runs without the TPS.

What Happens:

Under semi light throttle I'm getting a pretty severe case of the 3800 rpm hesitation.

Under WOT I have some low end hesitation that I'll attribute to the TB mod. However, it's almost like running into a temporary fuel cut between 3500 and 4k, as well as a few occasional hiccups even in the higher rpms.

I've added grounds to the ecu, and still experience the same hesitation. I have the boost sensor pill in. the 720's are brand new. Under WOT I'm hitting a/f numbers in the mid 10's. Rich, but not nearly enough to give the sometimes severe stumbles I'm getting. I never had any sort of hesitation problem before.



Reply
Old Jul 9, 2004 | 01:46 AM
  #2  
gsracer's Avatar
Thread Starter
EIT
Tenured Member 10 Years
 
Joined: Jan 2002
Posts: 1,790
Likes: 0
From: Austin, TX
Alcohol must have killed too many of my brain cells, I have indeed swapped out some of the vacuum tubing that imagine contained the restrictor pill.

After more driving I really don't think it's a case of 3800rpm hesitation just random hesitation across the entire rpm range. A good TPS should be on soon, and I'll see if I can locate a pill to stick in before the pressure sensor.

Other than the hesitation I'm very happy with both the e-manage and the bnr stage II turbo. Combined with the series 5 turbo and the TB mod, the turbo spools much quicker. I am running no boost controller, and in the higher gears I get about .1bar of creep from .4bar upwards to .5ish

The e-manage software is really easy to use, and not difficult to install at all. For other hybrid fc owners looking for more in depth management than a safc can offer I believe the e-manage is a great deal. With the e-manage, support tool, injector and ignition harness offered by www.mohdparts.com for 450, it's not that much more than a new safc II.

[/plug for e-manage]
Reply
Old Jul 14, 2004 | 04:15 AM
  #3  
gsracer's Avatar
Thread Starter
EIT
Tenured Member 10 Years
 
Joined: Jan 2002
Posts: 1,790
Likes: 0
From: Austin, TX
After plugging up the new TPS from Chris Sanders, the car runs great. I was under the impression that with the TPS removed, the ecu would revert to 100 percent throttle, so I'm still a little perplexed as to how the TPS removal actually caused hesitation problems (anyone remember kevin running his car with one removed).

I picked up the orifice that runs in line to the pressure sensor at the dealership today as well. Added grounds to the ecu, as well as the pressure sensor.

Result? The car runs absolutely great, and pulls amazingly hard for only .6bar.
Reply
Old Jul 15, 2004 | 12:02 AM
  #4  
mr_vaughn's Avatar
Chillin
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (1)
 
Joined: Feb 2002
Posts: 684
Likes: 5
From: LA,CA
Question AFM

what are you running for a Air Flow Meter ?
a s4 or s5???
is it before of after the turbo?

What are you using to tune for your wideband?
a LM-1 or FJO etc.?
Reply
Old Jul 15, 2004 | 12:06 AM
  #5  
gsracer's Avatar
Thread Starter
EIT
Tenured Member 10 Years
 
Joined: Jan 2002
Posts: 1,790
Likes: 0
From: Austin, TX
Re: AFM

Originally posted by mr_vaughn
what are you running for a Air Flow Meter ?
a s4 or s5???
is it before of after the turbo?

What are you using to tune for your wideband?
a LM-1 or FJO etc.?
s4 AFM, honestly I believe if anything the s4 could outflow the s5 AFM. I don't know about you, but that decreasing radius cone section looks pretty restrictive. I don't believe either will make a huge difference.

It's before the turbo, just you're generic 3'' TID->AFM->filter set up.

I'm currently using a plx-m300
Reply
Old Jul 15, 2004 | 12:14 AM
  #6  
BlackRx7's Avatar
Daily Domestic Killer
Tenured Member 10 Years
 
Joined: Mar 2001
Posts: 2,425
Likes: 0
From: San Antonio, Tx, USA
This is my exact problem currently, my TPS only goes from 0 ohms to 2800 then goes infinite...I have hesitation all across the rpm range if I'm at 1/2 throttle or less, otherwise WOT is pretty good.

gsracer -- who is this Chris Sanders guys does he have more TPS units?
Reply
Old Jul 15, 2004 | 12:19 AM
  #7  
gsracer's Avatar
Thread Starter
EIT
Tenured Member 10 Years
 
Joined: Jan 2002
Posts: 1,790
Likes: 0
From: Austin, TX
Originally posted by BlackRx7
This is my exact problem currently, my TPS only goes from 0 ohms to 2800 then goes infinite...I have hesitation all across the rpm range if I'm at 1/2 throttle or less, otherwise WOT is pretty good.

gsracer -- who is this Chris Sanders guys does he have more TPS units?
You probably know him better Banzai Racing, I'm sure he probably does.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
stickmantijuana
Microtech
5
Aug 23, 2015 11:04 AM
rx7brandon
General Rotary Tech Support
3
Aug 16, 2015 10:55 AM
KAL797
Test Area 51
0
Aug 11, 2015 03:47 PM




All times are GMT -5. The time now is 05:17 AM.