DIY: Throttle body bypass mod
Mu ha.. ha...
Joined: Aug 2004
Posts: 14,361
Likes: 3
From: Cali
Side Effect Caused by this Mod
I did this mod the simple way that TeamRX8 suggested, with the screw inserted into the coolant hose and put back on (works great by the way). I did this mod last winter and all has been well, engine seemed more responsive and all.
Here is the problem - on very hot days this summer after driving about 1.5 hours (I have a long commute), I noticed my car kept going into limp mode from detonation issues and I could not figure out why. I kept thinking all the traditional things, but what this wound up being, was this mod - let me explain.
I noticed that in the winter through not too hot months, the Throttle Body (TB) was actually cooler by having the coolant flow stopped. But on very hot days after long drives, the TB was getting extremely hot, even with my hood vent mod in place to keep the underhood temps down. This got me thinking, could it be this mod?
When I removed the screw and allowed the coolant to flow again, on many very hot days that I have driven since restoring the coolant flow, this detonation issue causing engine hesitation has NOT happened again (all the while running the same premium fuel and MMO premix)
What I have surmised, is that on very hot days and long drives, the coolant actually keep the TB cooler than it would be otherwise (although it does the opposite on cooler days), and thus it is heating the air entering the engine too much causing detonation issues.
If you live in a hot climate and/or are having detonation issues in hot weather and have this mod, you may want to reverse this mod to see if it cures the issue.
One last thing, if you use Team's method (it takes 30 second to put in and 30 seconds to remove) instead of permanently moving your hose configuration, this is easy to put in place for most of the year (cooler months) and removing during the hot months.
Hopefully this will helps others that may have come across the same issue.
I did this mod the simple way that TeamRX8 suggested, with the screw inserted into the coolant hose and put back on (works great by the way). I did this mod last winter and all has been well, engine seemed more responsive and all.
Here is the problem - on very hot days this summer after driving about 1.5 hours (I have a long commute), I noticed my car kept going into limp mode from detonation issues and I could not figure out why. I kept thinking all the traditional things, but what this wound up being, was this mod - let me explain.
I noticed that in the winter through not too hot months, the Throttle Body (TB) was actually cooler by having the coolant flow stopped. But on very hot days after long drives, the TB was getting extremely hot, even with my hood vent mod in place to keep the underhood temps down. This got me thinking, could it be this mod?
When I removed the screw and allowed the coolant to flow again, on many very hot days that I have driven since restoring the coolant flow, this detonation issue causing engine hesitation has NOT happened again (all the while running the same premium fuel and MMO premix)
What I have surmised, is that on very hot days and long drives, the coolant actually keep the TB cooler than it would be otherwise (although it does the opposite on cooler days), and thus it is heating the air entering the engine too much causing detonation issues.
If you live in a hot climate and/or are having detonation issues in hot weather and have this mod, you may want to reverse this mod to see if it cures the issue.
One last thing, if you use Team's method (it takes 30 second to put in and 30 seconds to remove) instead of permanently moving your hose configuration, this is easy to put in place for most of the year (cooler months) and removing during the hot months.
Hopefully this will helps others that may have come across the same issue.
Open hood touch TB. No mod you get burned. With mod almost but no burn.
Plus never had detenation on track days with TB mod.
Detailed DIY Throttle body bypass
So I did the throttle body bypass mod today and it is SIMPLE. But for those of you who are not so mechanically inclined here is a very detailed DIY (Make sure the coolant is cold and the car has been sitting for a while before doing this mod. Also you may want to remove the rad cap to release the pressure in the coolant system):
1. Remove top coolant hose from throttle body.
2. Remove the intake tubing and the 4 throttle body bolts.
3. Remove the wire harness on the throttle body and the last hose holding it to the car will be the bottom coolant line.
4. Remove the lower coolant line from the throttle body also.
5. You can then remove the throttle body and cap the coolant nipples. (Optional)
1. Remove top coolant hose from throttle body.
2. Remove the intake tubing and the 4 throttle body bolts.
3. Remove the wire harness on the throttle body and the last hose holding it to the car will be the bottom coolant line.
4. Remove the lower coolant line from the throttle body also.
5. You can then remove the throttle body and cap the coolant nipples. (Optional)
Detailed DIY Throttle body bypass continued
6. You can now pull the two coolant lines to the passenger (right) side of the alternater.
7. The top hose can be cut shorter so it fits nicely with the bottom coolant hose (about 6-7 inches cut off).
8. Now you can install the 5/16 brass barb into the lines along with the hose clamps.
9. You can then tuck the hose into a nice, out of the way, clean looking location.
7. The top hose can be cut shorter so it fits nicely with the bottom coolant hose (about 6-7 inches cut off).
8. Now you can install the 5/16 brass barb into the lines along with the hose clamps.
9. You can then tuck the hose into a nice, out of the way, clean looking location.
eazyryder
Joined: May 2008
Posts: 68
Likes: 0
From: totonto canada
hey i think this might be a dumb question but here goes...is it possible to bypass the maf sensor?.....
my car idle goes up and down i kinda sound like the timing is not right but if i take out the maf sensor and start it the car idles fine but i have to really rev it on the start up...
my car idle goes up and down i kinda sound like the timing is not right but if i take out the maf sensor and start it the car idles fine but i have to really rev it on the start up...
Detailed DIY Throttle body bypass continued
10. Replace the throttlebody and the intake tubing. Remember to hook up the wire harness and tighten the hose clamp on the intake tube. DO NOT tighten the throttle body bolts too much or you will strip them or even snap a head off!
This mod so far has not made any real noticable changes. Although this week has been cool and rainy up here on the prairies and it was only about 18C outside (64F for you American fellas).
The last picture is all the tools I used for the job and the left over materials from the car. Believe it or not it actually took me longer to write this up then to start and complete this mod.
Beers!
Jesse A.
This mod so far has not made any real noticable changes. Although this week has been cool and rainy up here on the prairies and it was only about 18C outside (64F for you American fellas).
The last picture is all the tools I used for the job and the left over materials from the car. Believe it or not it actually took me longer to write this up then to start and complete this mod.
Beers!
Jesse A.
I wouldn't, as long as its not stalling on you it is fine if it is bouncing a little bit. The MAF is needed to tell your ECU how much fuel to inject relative to the amount of air coming into the engine. Put it back on ASAP
Registered User
Joined: Oct 2004
Posts: 1,141
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Just as a FYI, the feed coolant line is the one that is difficult to get to. The return line is the one at the top. So putting a screw to block the return line is not going to help you at all. Plus it's a much better idea to keep the system looped
Super Moderator
Joined: Apr 2005
Posts: 10,880
Likes: 339
From: Australia
Yep, the feed (coolant) line is down by the thermostat RH side of car (Passenger LH Drive).
Registered User
Joined: Oct 2004
Posts: 1,141
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I spent 1.5 hours to do this mod. I seriously doubt it will make any real difference unless you are running in some super hot condition. I did do my lines in a way that I can loop it back easily, I guess I can always mess with it to see if it helps. The next time I run my car, I will hook up the datalogger to see what I can find
Registered User
Joined: Oct 2004
Posts: 1,141
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I don't have enough data to backup the performance gain yet (no time to sort through the data), but there is definitely a noticeable different in the temperature of the throttle body. Another RX-8 and mine did 15 minutes straight, his TB was basically too hot to touch while you could place a hand on mine. I don't know how they translate in time, but it can't hurt right. I did route mine in a way that I could always swap back to stock easily
I've had this mod done on the car since I bought it (used in 2008). I drove it all winter with no problems, but had no real gains in the summer. In fact, I was running a little hot while autocrossing. . . but I can't confirm or deny that it had anything to do with it.
I did this mod before, but when my engine was swapped they undid it 
. I rarely had the coolant light come on before even on 100+ degree days....now it comes on once the weather hits 90+ unless I shift to be in lower rpm's or let off the engine load. I will do this mod again before next summer. Its starting to cool down so its pointless for the time being.
. I rarely had the coolant light come on before even on 100+ degree days....now it comes on once the weather hits 90+ unless I shift to be in lower rpm's or let off the engine load. I will do this mod again before next summer. Its starting to cool down so its pointless for the time being.
well, when you mention it like that. I've never had my coolant light come on. Even on 100 degree days. (yes, it gets to be 100 in Ohio about once or twice a summer)
I've put about 8,000 miles on since the mod. All i did was put a sheetrock screw into the TB, and put the hose back on top, works ingeniously actually aha.
No problems, runs perfect. I can put my hand on the TB afterwards a longer drive, copared to the scolding surrounding areas.
No problems, runs perfect. I can put my hand on the TB afterwards a longer drive, copared to the scolding surrounding areas.
Registered User
Joined: Oct 2004
Posts: 1,141
Likes: 0
I've put about 8,000 miles on since the mod. All i did was put a sheetrock screw into the TB, and put the hose back on top, works ingeniously actually aha.
No problems, runs perfect. I can put my hand on the TB afterwards a longer drive, copared to the scolding surrounding areas.
No problems, runs perfect. I can put my hand on the TB afterwards a longer drive, copared to the scolding surrounding areas.
Super Moderator
Joined: Apr 2005
Posts: 10,880
Likes: 339
From: Australia
Genuine Blanking-OFF Caps for TB, to STOP COOLANT FLOW
Had someone ask me about Genuine Mazda Blank-off Caps for the TB..
This is for those who remove the entire TB Coolant Supply and Return lines/hoses.
You use the existing Hose Clamps (B6BF-15-538) for these Caps.
The Genuine Blank-Off Cap Part Number is FEA7-13-104 they are about $5 each.
If you want to do the remove properly you need minimum 2 maximum of 4 caps..
One Cap goes on just below Thermostat Housing, the other about 10 inches away (above thermostat) on top of the REAR Black Rotor Iron..
Capping these two will stop the supply of coolant to the TB.
The other two caps can be used to Blank off the In and Out on the TB itself.
Again you use the original Hose clamps.
So 4 caps will totally remove the Coolant to your TB.
And you can remove the two TB Hoses also.
Just remember this is a permanent fix, if you want to heat your TB you will have to reverse the above.
This is for those who remove the entire TB Coolant Supply and Return lines/hoses.
You use the existing Hose Clamps (B6BF-15-538) for these Caps.
The Genuine Blank-Off Cap Part Number is FEA7-13-104 they are about $5 each.
If you want to do the remove properly you need minimum 2 maximum of 4 caps..
One Cap goes on just below Thermostat Housing, the other about 10 inches away (above thermostat) on top of the REAR Black Rotor Iron..
Capping these two will stop the supply of coolant to the TB.
The other two caps can be used to Blank off the In and Out on the TB itself.
Again you use the original Hose clamps.
So 4 caps will totally remove the Coolant to your TB.
And you can remove the two TB Hoses also.
Just remember this is a permanent fix, if you want to heat your TB you will have to reverse the above.
is looking for his torque
Joined: Sep 2008
Posts: 841
Likes: 0
PITA PITA PITA PITA.
feel anything? no.
but it felt good finishing lol (thats what she said)
im sure it will pay off in the end. tips:
10mm for throttle body, wrech wont work, need an extension like that yellow rx8.
impossible to do without removing throttle body, while its out clean it up with some de greaser.
and last, you can cut off a lot more than 7inch on the top wire, i cut atleast a foot off, with room to spare, PLEASE get 5/16" checked 2 stores, had to settle for 3/8" its a pain to put it on. especially when you have ocd and you want it on all the way
feel anything? no.
but it felt good finishing lol (thats what she said)
im sure it will pay off in the end. tips:
10mm for throttle body, wrech wont work, need an extension like that yellow rx8.
impossible to do without removing throttle body, while its out clean it up with some de greaser.
and last, you can cut off a lot more than 7inch on the top wire, i cut atleast a foot off, with room to spare, PLEASE get 5/16" checked 2 stores, had to settle for 3/8" its a pain to put it on. especially when you have ocd and you want it on all the way
I've been meaning to do this for a while so i did it today. It was pretty easy. The 3/8 fitting wasn't too tight but it wasn't easy.
I didn't really do the before and after touch test for myself but i have touched the TB after a 25 min track session and that pretty much burned my finger off.
So for a comparo i went for a drive came back, popped the hood, touched the TB which i found to be not hot at all and then touched the brass fitting and screw clamp which, yes, almost burnt my finger off (
ok maybe not that bad but it was very hot)
I didn't really do the before and after touch test for myself but i have touched the TB after a 25 min track session and that pretty much burned my finger off.
So for a comparo i went for a drive came back, popped the hood, touched the TB which i found to be not hot at all and then touched the brass fitting and screw clamp which, yes, almost burnt my finger off (
ok maybe not that bad but it was very hot)