YotaTech Forums  

Go Back   YotaTech Forums > Toyota SUV & Truck Tech > 86-95 Trucks & 4Runners
Sign in using an external account
Register Forgot Password?
Search


86-95 Trucks & 4Runners 2nd/3rd gen pickups, and 1st/2nd gen 4Runners with IFS

Welcome to Yotatech!
Welcome to Yotatech,

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!


Reply
 
LinkBack Thread Tools Search this Thread
Old 01-26-2007, 10:40 AM   #1 (permalink)
Registered User
Personal Sales Rating: (0)
 
Lifelongtoy's Avatar
 
Join Date: Jan 2007
Location: In my drivers seat
Posts: 253
Question what happens with disconnected TPS

Simple question, What happens if the TPS is not hooked up? How will the engine run? More specifically, engine started running like crap, felt like it was missing and had very little power. And it will die at idle. Even going 65 with and warmed up, if I put in neutral and let off the gas it dies. Help, thanks.
This ad is not displayed to registered members.
Register your free account today and become a member on Yotatech!
Lifelongtoy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-26-2007, 10:42 AM   #2 (permalink)
Contributing Member
Personal Sales Rating: (0)
 
mastacox's Avatar
 
Join Date: Dec 2003
Location: Fort Worth, TX
Posts: 2,874
Have you checked for any vacuum leaks?
__________________
Brian

1998 4Runner SR5
Supercharged, URD'd, Lifted, etc. etc.

2006 VW Jetta TDI- 50mpg highway cruiser
mastacox is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-26-2007, 10:48 AM   #3 (permalink)
Registered User
Personal Sales Rating: (0)
Threadstarter [OP]
 
Lifelongtoy's Avatar
 
Join Date: Jan 2007
Location: In my drivers seat
Posts: 253
Almost 100% no vacume leak, but it definetly feels like one.
Lifelongtoy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-26-2007, 10:50 AM   #4 (permalink)
Contributing Member
Personal Sales Rating: (0)
 
mastacox's Avatar
 
Join Date: Dec 2003
Location: Fort Worth, TX
Posts: 2,874
Standard quick stuff probably is a good idea- spark plugs, wires, air filter, check fluids, etc...
__________________
Brian

1998 4Runner SR5
Supercharged, URD'd, Lifted, etc. etc.

2006 VW Jetta TDI- 50mpg highway cruiser
mastacox is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-26-2007, 11:19 AM   #5 (permalink)
Registered User
Personal Sales Rating: (0)
 
Join Date: Jul 2004
Location: Alexandria, VA
Posts: 139
car should start and idle w/ the TPS disconnected, but it'll die as soon as you touch the throttle.
__________________
James
'95 4Runner V6
33" TrXus / LC coils / BJ spacers
Marlin armor and Warn winch
jht3 is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-26-2007, 11:59 AM   #6 (permalink)
Sponsoring Member
Vendor Sales Rating: (0)
 
midiwall's Avatar
 
Join Date: Dec 2002
Location: Seattleish, WA
Posts: 9,048
Quote:
Originally Posted by jht3 View Post
car should start and idle w/ the TPS disconnected, but it'll die as soon as you touch the throttle.
I disconnected mine once to test someone's theory about why a SplitSecond black box wasn't working.

So, with the understanding that I'm in a 3rd gen with a 3.4L, mine idled and ran "okay' up to about 2000RPM. Under load it had no power, and no throttle response above that 2k mark.
__________________
~ Mark
'96 4Runner Limited S/C MI - 370cc injectors, Air! horns, Airaid MIT, ATS A-arms, 285/75/R16 BFG MTs, Bored TB, Brembo slotted, Cobra 75 WXST, Deckplate, Downey headers, Hayden cooler, IPT valve body, Level 10 torque convertor, Meanstreak exhaust, OME/OME rears, On-board PC (XM, Nav, WiFi, etc), Port 'n Polish, Remote Start, SAW fronts, Hilux console, SMT-5, Stubb's sliders, Supra MAF, TJM-17, 2.0" pulley, Viair 450c, Walbro 190, Weasy2k cams

Last edited by midiwall; 01-26-2007 at 12:19 PM.
midiwall is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-26-2007, 12:13 PM   #7 (permalink)
Registered User
Personal Sales Rating: (0)
 
sloth!'s Avatar
 
Join Date: Dec 2005
Location: central CA
Posts: 81
if your tps was disconnected you would get a CEL. Have you checked for CEL codes lately? Have you checked the air tube between the AFM and the throttle body for leaks?
__________________
90 xcab, sased, arbs, 37s, marlin dual cases, warn, longfeilds, bobbed, ready for the mall.

94 4x4 DD

06 tundra CC 4x4
sloth! is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-26-2007, 12:50 PM   #8 (permalink)
Registered User
Personal Sales Rating: (0)
Threadstarter [OP]
 
Lifelongtoy's Avatar
 
Join Date: Jan 2007
Location: In my drivers seat
Posts: 253
I havent checked for codes because the light doesent come on. Should I try to pull them anyway? Im looking really hard to try to find some air leak because that is what it feels like.

You mentioned fluids, would a low fluid level cause this kind of problem (stumbling during acceleration, loss of power).
Lifelongtoy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-26-2007, 02:09 PM   #9 (permalink)
Registered User
Personal Sales Rating: (0)
 
Join Date: Jun 2006
Location: Mooresville, NC
Posts: 263
Send a message via AIM to Firefightertaco
Does your CEL work? when u start your car up it should come on for a few seconds just to show u that the bulb isnt burnt out.
__________________
JP
2003 Tacoma TRD
2007 fj
Firefightertaco is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-26-2007, 02:15 PM   #10 (permalink)
Registered User
Personal Sales Rating: (0)
Threadstarter [OP]
 
Lifelongtoy's Avatar
 
Join Date: Jan 2007
Location: In my drivers seat
Posts: 253
If that is the only test to see if it works, then yeah the light does come on for a few seconds. Any thoughts would be great cause iv been at it for days.
Lifelongtoy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-26-2007, 02:40 PM   #11 (permalink)
Registered User
Personal Sales Rating: (0)
 
toyotaoffroad91's Avatar
 
Join Date: Mar 2005
Location: long island, NY
Posts: 343
transmission will not shift properly either
__________________
91 pickup 22RE, 5 speed swap, 35x12.5 TriXuS M/T-SOLD!
96 4Runner Limited-FOR SALE!
07 FJ
toyotaoffroad91 is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-26-2007, 02:54 PM   #12 (permalink)
Registered User
Personal Sales Rating: (0)
Threadstarter [OP]
 
Lifelongtoy's Avatar
 
Join Date: Jan 2007
Location: In my drivers seat
Posts: 253
Manual transmission shifts just fine. Starts up everytime, even when it 30 degree outside. burning fuel a little quicker.
Lifelongtoy is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-26-2007, 03:08 PM   #13 (permalink)
Contributing Member
Personal Sales Rating: (0)
 
rdharper's Avatar
 
Join Date: May 2006
Location: Morgan Hill, Ca
Posts: 1,066
Quote:
Originally Posted by Lifelongtoy View Post
Simple question, What happens if the TPS is not hooked up? How will the engine run? More specifically, engine started running like crap, felt like it was missing and had very little power. And it will die at idle. Even going 65 with and warmed up, if I put in neutral and let off the gas it dies. Help, thanks.
On my 2nd generation, disconnecting the TPS threw a code, but the truck ran perfectly.

If the TPS is not adjusted correctly as evidenced by a 500rpm idle, and hesitation with initial acceleration, unplugging the TPS connector should then cause a correct idle, and a normal acceleration.

Correcting the TPS then produced a correct idle, and no code.

Granted that is based on my experience, and the experience of several others with whom I've had exchanges.

Apparently others have had different experiences.

Be nice to have more data.
__________________
Richard

"Science by consensus... is not Science." Richard Harper -1988

'94 Toyota 4Runner V6 3L 158K miles 14mpg
'85 Toyota 22rec 4WD SR5 LB PU 208K miles 18mpg
'08 Honda Ridgeline RT 4.8K miles 16mpg
'06 Honda Rincon ATV 410miles/65hrs 22 mpg
rdharper is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-27-2007, 10:20 PM   #14 (permalink)
Registered User
Personal Sales Rating: (0)
 
Join Date: Jul 2006
Posts: 101
Quote:
Originally Posted by rdharper View Post
On my 2nd generation, disconnecting the TPS threw a code, but the truck ran perfectly.


Apparently others have had different experiences.

Be nice to have more data.
I disconnected mine for a day once in a misguided troubleshooting attempt. It ran as well without it, but caveat here is that I already had a CEL for the knock sensor. Anyways - my 1990 3vze ran OK without the tps connected - however I suspect that it was already running in "failsafe mode"
BC Rider is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-28-2007, 02:43 AM   #15 (permalink)
Contributing Member
Personal Sales Rating: (0)
 
rdharper's Avatar
 
Join Date: May 2006
Location: Morgan Hill, Ca
Posts: 1,066
Quote:
Originally Posted by BC Rider View Post
I disconnected mine for a day once in a misguided troubleshooting attempt. It ran as well without it, but caveat here is that I already had a CEL for the knock sensor. Anyways - my 1990 3vze ran OK without the tps connected - however I suspect that it was already running in "failsafe mode"
Interesting. For the record, I had no codes prior to the disconnect. My symptoms prior to fixing the TPS were low RPM, and hesitation on initial acceleration.

I would think "fail safe" mode would be pretty miserable performance, although I couldn't find enough information on it to know one way or another. Neither for 2nd generation, or in general.
__________________
Richard

"Science by consensus... is not Science." Richard Harper -1988

'94 Toyota 4Runner V6 3L 158K miles 14mpg
'85 Toyota 22rec 4WD SR5 LB PU 208K miles 18mpg
'08 Honda Ridgeline RT 4.8K miles 16mpg
'06 Honda Rincon ATV 410miles/65hrs 22 mpg
rdharper is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-28-2007, 09:45 AM   #16 (permalink)
Registered User
Personal Sales Rating: (0)
 
Join Date: Jul 2006
Posts: 101
Quote:
Originally Posted by rdharper View Post
I would think "fail safe" mode would be pretty miserable performance, although I couldn't find enough information on it to know one way or another. Neither for 2nd generation, or in general.
You're right - my truck was already running poorly - but ran no worse after the tps disconnect. I already had a code 52 which apparently retards the timing to a safe value to prevent pinging. I've probably used the term "failsafe" incorrectly here - should of been more specific.
BC Rider is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-28-2007, 11:17 AM   #17 (permalink)
Contributing Member
Personal Sales Rating: (0)
 
rdharper's Avatar
 
Join Date: May 2006
Location: Morgan Hill, Ca
Posts: 1,066
Quote:
Originally Posted by BC Rider View Post
You're right - my truck was already running poorly - but ran no worse after the tps disconnect. I already had a code 52 which apparently retards the timing to a safe value to prevent pinging. I've probably used the term "failsafe" incorrectly here - should of been more specific.
Ok, that makes sense. That fits with what I believe is accurate.. ie: if you disconnect the TPS and performance improves, then the TPS is not working correctly. Failure of the throttle to fully return to its physical stops, or misadjustment (I believe) is the most common fault, failure of the TPS or wiring, second most likely.
__________________
Richard

"Science by consensus... is not Science." Richard Harper -1988

'94 Toyota 4Runner V6 3L 158K miles 14mpg
'85 Toyota 22rec 4WD SR5 LB PU 208K miles 18mpg
'08 Honda Ridgeline RT 4.8K miles 16mpg
'06 Honda Rincon ATV 410miles/65hrs 22 mpg
rdharper is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 01-28-2007, 11:17 AM
Yotatech
4WD Truck




Paid Advertisement
Reply

Tags
97, disconnected, engine, failure, jetta, ping, position, runs, sensor, symptoms, tdi, test, testing, throttle, tps

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 Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
84 22r Disconnected Vacuum Lines Sensors/Switches mrongey 84-85 Trucks & 4Runners 5 06-29-2007 09:44 PM
Risks of driving W/ sway bars disconnected? 2wheelBLACKOUT Offroad Tech 13 05-02-2005 09:55 PM
Tps desert whomper 95.5-2004 Tacomas & 96-2002 4Runners 2 01-17-2005 09:40 AM
No, my truck is not haunted...or...why my stereo comes on when battery disconnected scott.475 95.5-2004 Tacomas & 96-2002 4Runners 2 11-12-2004 04:10 PM
O2 sensor disconnected should it trip a code always? Lonny007 95.5-2004 Tacomas & 96-2002 4Runners 2 05-05-2003 10:56 AM


All times are GMT -8. The time now is 06:40 PM.


2010 InternetBrands, Inc.

Search Engine Friendly URLs by vBSEO 3.5.2