Engine slowly losing power

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Engine slowly losing power

Postby egrant5329 » Sat Sep 08, 2018 2:28 pm

Lately while running the spyder out on the roads the car seemed like it didn't have the power it used to have. When I would go to pass a car and they floor it to mess with me as cars often do, I was barely pulling ahead of them. It has been bugging me wondering why. Today while messing around with my ignition MAP I was putting the pedal to the floor fairly frequently trying to make sure there wasn't any pinging. Low and behold, I found my problem.

On the CB crank trigger setup there is a screen that allows you to see all of the realtime data instead of the main computer screen that mainly shows RPM and advance. Watching the realtime data, I found the issue. My TPS was showing only 35% with my pedal to the floor. ](*,) I unhooked the throttle cable and set the min/max on the TPS, hooked the cable back up and it was still at 35%. After more investigation, the front cable mount was loose. After tightening everything back up, I checked the TPS reading and it would go from 1 to 98%.
It's amazing how much better the car runs when you actually get full throttle! :nana:

This happened to me years ago and I had forgotten about it so thought I would post it just for fun. #-o
EdG
Last edited by egrant5329 on Mon Sep 10, 2018 8:44 am, edited 1 time in total.
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Re: Engine slowly loosing power

Postby DannyP » Sat Sep 08, 2018 3:53 pm

I had a similar problem, but mine was slightly different. I hooked up the computer, and the TPS was jerky and jumpy and no longer reached 100%. My throttle did, but not the TPS. I tried to clean it, but my OE 1990 Ford Escort TPS crapped out. I replaced it then recalibrated for the new one and good to go. This happened in the spring. The part only lasted 28 years......
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Re: Engine slowly loosing power

Postby EEricson » Sun Sep 09, 2018 3:45 pm

The loose cable issue was the first one Franny went after in the fix-a-spyder videos.
https://www.youtube.com/watch?v=oB5bkWHoymU
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Re: Engine slowly loosing power

Postby DannyP » Mon Sep 10, 2018 7:28 am

Always make sure you have some play at idle, and make sure the full throttle stop is set. Otherwise you could twist the throttle shafts in the carbs. Very bad.

The idle play is there to prevent idle speed rising as the cable housing expands with engine heat. Ask me how I know......
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Re: Engine slowly losing power

Postby egrant5329 » Mon Sep 10, 2018 8:43 am

I have the CSP bell crank linkage and I really like that I never have issues with it, but I really dislike my throttle cable setup. The cable works fine, but it makes a long loop running to the back of the car, gently turning and then going through the standard housing location. I have considered going back to a modified cross bar linkage so I could run the cable right up the front of the engine instead of the back of the engine. As far as I can tell there isn't an easy way to do that on the bell crank linkage.

Bernie Bergman has an nice clean bearing setup for the crossbars http://bergmannvw.net/Website-New/pages ... kages.html Apparently it doesn't work for the Redline linkage that I have on my parts shelf. I inquired about just buying the entire setup and he didn't want to sell it to me saying that I should stay with what I have because there is wear and tear on the carbs. I thought that was a bit odd of him to say. The carbs were a bit dirty (I drive dirt roads all the time), but there isn't that many miles on the carbs.

I may get excited and do the heim modification on my old redline linkage at some point.
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