car bogging in low rpms and take off

natedogr

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Sep 12, 2006
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Chatham, Va
i've got my car running finally with a fully rebuilt 7mgte swap, was a NA. the first test drive the car pulled amazing just like it should and was making 10psi with no controller. well since that first drive i've done a few things to it and now its bogging really bad when i first take off from a stop. it drives like that for a good while until it gets in to the higher rpms. the only code i was getting was 51 and i fixed that and it does the same thing. i also fixed all my boost leaks but it bogs the exact same and i was only seeing 5psi or so. i haven't changed out the fuel pump since i did the swap though so i thought that might be it. but i'm confused because it drove so well that first drive and now this. i had to change the front main since the first drive but i did everything right. any ideas?
 

jdub

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Recheck cam gear and damper alignment at TDC...you might have jumped a timing belt tooth. Especially if you did not replace the tensioner spring ;)
 

natedogr

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Sep 12, 2006
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i was going to check all that this weekend. the tensioner was brand new when i rebuilt the motor, i wouldn't have to replace that after doing the front main would i?
 

jdub

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It should still be good...I would still check to make sure it didn't jump a tooth. Sure you tightened it down? You should always do a tension adjustment after 500 miles or so.
 

natedogr

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Sep 12, 2006
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i'm pretty sure we got the belt on there right. i will def check this weekend though and the tensioner. i've only driven the car 70 miles maybe since the rebuild :biglaugh:. its crazy the difference between the first drive and now. its driving slower right now than my NA did...
 

natedogr

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Sep 12, 2006
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my dad just checked the timing and it was way off, forgot what he said it was at. he said he still couldn't get it quite to 10 degrees though. he took it out for a drive and it was sooo much better. so a little bit more adjusting i suppose.
 

jdub

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Figured it was timing...with the cam gears pointing at the index marks and the damper pointing at zero (#1 piston at TDC), the CPS should look like this:

CPS Align.jpg


It's pretty easy to get the CPS off by a tooth following the TSRM procedure.
 

natedogr

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Sep 12, 2006
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i'll keep this in mind and take a look at it. thats probably what's keeping him from getting it right at 10 degrees. thats what it should be at right?
 

natedogr

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well i checked my cam gears when the crank was at TDC and you were right jdub my belt jumped a tooth. the cam gears weren't lined up like they were supposed to. but i guess it wasn't too far off since the car would run and all. got them lined back up, set my timing and she runs flawless now. thanks for the help jdub!
 

jdub

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Make sure the tensioner is set correctly and the retainer nut torqued to spec....check it again in 500 miles or so.

You're welcome ;)
 

IJ.

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natedogr;1395418 said:
well i checked my cam gears when the crank was at TDC and you were right jdub my belt jumped a tooth. the cam gears weren't lined up like they were supposed to. but i guess it wasn't too far off since the car would run and all. got them lined back up, set my timing and she runs flawless now. thanks for the help jdub!
A LOT of our members could learn from this post!
 

supramk388

3.1 Supra T78
Mar 31, 2005
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jdub;1392997 said:
Figured it was timing...with the cam gears pointing at the index marks and the damper pointing at zero (#1 piston at TDC), the CPS should look like this:

CPS Align.jpg


It's pretty easy to get the CPS off by a tooth following the TSRM procedure.

This was awesome jdub, thanks. My 91 is running very poorly. I dropped the tranny and put OS Giken clutch this weekend. Since I was working I checked timing and not sure how but my cam gears were way off. So I got everything at TDC and better but still off some. After seeing your post this is exacty the issue I am having. I will try this tomorrow afternoon see how it goes.

Its been a while but getting back in it jdub, I will call you in a few weeks catch up on things.
 
Last edited:

jdub

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