Throttle cannot stay steady and goes between idle and 2000 RPM

Tiny
PENNETTIMOM
  • MEMBER
  • 1988 TOYOTA SUPRA
  • 80,000 MILES
1988 toyota supra - at 2000 rpm Have replaced air manifold meter and all hoses. Problem started after a hose burst. Car did not overheat. Replaced that hose and went ahead (due to age) replaced all hoses. When driving slowly (such as parking lots), car bucks badly at about 5-10mph/2000 rpm. Did some research and determined it might be the air manifold. Replaced that. Some improvement -bucking was not so prominent, but car cannot maintain steady rpm.

Have taken to four mechanics in the (DC) area, none have been able to figure it out. \ I just want to enjoy the car as I have for almost 24 years.
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Saturday, January 28th, 2012 AT 9:38 PM

8 Replies

Tiny
RASMATAZ
  • MEMBER
Carbuerator or EFI fuel system?
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Saturday, January 28th, 2012 AT 9:40 PM
Tiny
PENNETTIMOM
  • MEMBER
Electronic fuel injection
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Saturday, January 28th, 2012 AT 10:00 PM
Tiny
RASMATAZ
  • MEMBER
Clean and test the idle air control valve, EGR and PCV valves-also test the MAF and TPS sensor-to include a fuel pressure/vacuum leak-check-start here
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Saturday, January 28th, 2012 AT 11:02 PM
Tiny
PENNETTIMOM
  • MEMBER
Thank you. I had thought something like this, but had no idea where to start. You've given me some starting points and I really appreciate it.

Please notify your web site that I could not get a donation to go through. I was using a credit card (not pay pal) and it kept telling me I had not input the: expiration date of card and type of card. I tried four times. Each time making sure it was on the form and correct, but after submitting, it's like the form reset those fields. I will still make the donation, just need a fix to this.
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Sunday, January 29th, 2012 AT 6:11 PM
Tiny
MHPAUTOS
  • EXPERT
Does this model have a water heated throttle body?
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Sunday, January 29th, 2012 AT 11:48 PM
Tiny
PENNETTIMOM
  • MEMBER
Truthfully, I'm sure what a water heated throttle body is, so I will say no. This is a 1988; maybe the 90's versions had it.
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Monday, January 30th, 2012 AT 2:34 AM
Tiny
RASMATAZ
  • MEMBER
Have you checked what I've suggested?
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Monday, January 30th, 2012 AT 2:46 AM
Tiny
PENNETTIMOM
  • MEMBER
No, it's winter here and my garage is not heated and I'm in the middle of renovating my kitchen. It will probably be two to four weeks before I can get through everything.
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Monday, January 30th, 2012 AT 5:27 AM

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