Poor power below 3000 RPM

AustinTXMk1 · 07-02-2009, 11:34 AM

I am trying to figure out what might be causing a power issue on my 85 Mk1 when at low rpm. The mil has about 325K miles on it, but generates good power between 3000 on up when you ask it to.

Another issue I seem to have is that once you been on it or it's been at speed for a while, and you come to a stop, it generally wants to stall.

Timing is good, idle speeds are good, what else should I be considering.

Compression is within spec and within 5% across all cylinders, it is comsuming some oil and I believe this is valve train related. I'm open to suggestions and wisdom from this board - surely this has been seen before...

AustinTXMk1 · 07-02-2009, 11:39 AM

Any guidance on where to search for replacement bumper components? I am in need of front for sure bumper cover (broken in several places) and would like to replace the rear cover as well. Haven't taken them off completely yet so don't know what else I'm in need of but would like to get an idea as to where to focus my search. Some parts are still available from Toyota, but can I do better aftermarket?

Open to suggestions...

palos · 07-02-2009, 12:03 PM

Congrats on the longevity of your car.

I would recommend performing a tune-up on the car, or checking everything that ordinarily would be changed or adjusted when doing one. Also, I would make certain that the air flow meter and throttle body are clean. Perhaps adding an additive to try to clean the fuel injectors would help.

The stalling after you have been up to speed is likely air in the cooling system, or perhaps a non-properly adjusted throttle positioning sensor. Best guess is the former, in which case bleeding the system should help.

At a certain point, I think you will need to evaluate the costs/benefits of putting additional funds into the car versus buying another with fewer miles. I'm certain many parts are worn, fatigued, etc…

07-02-2009, 11:34 AM	#1 (permalink)
AustinTXMk1 Intermediate/ Adv Skills Join Date: Jun 2009 Location: Austin, TX Posts: 22 Thanks: 4 Thanked 0 Times in 0 Posts iTrader Rating: (1/100% )	Poor power below 3000 RPM I am trying to figure out what might be causing a power issue on my 85 Mk1 when at low rpm. The mil has about 325K miles on it, but generates good power between 3000 on up when you ask it to. Another issue I seem to have is that once you been on it or it's been at speed for a while, and you come to a stop, it generally wants to stall. Timing is good, idle speeds are good, what else should I be considering. Compression is within spec and within 5% across all cylinders, it is comsuming some oil and I believe this is valve train related. I'm open to suggestions and wisdom from this board - surely this has been seen before...

07-02-2009, 11:39 AM	#2 (permalink)
AustinTXMk1 Intermediate/ Adv Skills Join Date: Jun 2009 Location: Austin, TX Posts: 22 Thanks: 4 Thanked 0 Times in 0 Posts iTrader Rating: (1/100% )	Bumper Parts - 1985 Mk1 Any guidance on where to search for replacement bumper components? I am in need of front for sure bumper cover (broken in several places) and would like to replace the rear cover as well. Haven't taken them off completely yet so don't know what else I'm in need of but would like to get an idea as to where to focus my search. Some parts are still available from Toyota, but can I do better aftermarket? Open to suggestions...

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07-02-2009, 12:03 PM	#3 (permalink)
palos … Join Date: Apr 2009 Posts: 170 Thanks: 0 Thanked 20 Times in 18 Posts iTrader Rating: (0/0% )	Congrats on the longevity of your car. I would recommend performing a tune-up on the car, or checking everything that ordinarily would be changed or adjusted when doing one. Also, I would make certain that the air flow meter and throttle body are clean. Perhaps adding an additive to try to clean the fuel injectors would help. The stalling after you have been up to speed is likely air in the cooling system, or perhaps a non-properly adjusted throttle positioning sensor. Best guess is the former, in which case bleeding the system should help. At a certain point, I think you will need to evaluate the costs/benefits of putting additional funds into the car versus buying another with fewer miles. I'm certain many parts are worn, fatigued, etc…