Throttle problem after DPFI to MPFI swap
#1
Junior Member
Thread Starter
Join Date: May 2008
Location: OM NOM NOM
Posts: 45
Likes: 0
Received 0 Likes
on
0 Posts
Throttle problem after DPFI to MPFI swap
So after I swapped my D16A6 into my Civic CX, I noticed that between shifts it would take approx. 2 to 3 seconds for the revs to drop. I've cleaned the throttle body, EACV and I replaced the throttle cable with a brand new SI one. Now here's the thing, this problem only happens when the engine is warm. With no load the problem is still there. The throttle opens and closes no problem. I've checked the pedal assembly, checked for vacuum leaks and the throttle cable adjustment. No problems! The FITV isn't plugged in, would that cause the problem? Any help would be great
thanks
edit: the setup if it helps
- D16A6 with 200, xxx km's into a Civic CX hatch using the fourthgenhatch.net DPFI to MPFI tutorial
- 4-2-1 headers
- crush bent exhaust
- I replaced the fuel filter, timing belt and water pump when I did the swap, plus the cam, crank and rear main seal
- All the connections are soldered and heat shrinked
The car runs great and has good power (I was driving with the D15B2 for more than a year!) but the only problem is a grind going into 5th gear (GM synchromesh fixed it.. for now) and the slow rev dropping between gears.
Yes, the wiring looks like ****, I'm leaving it exposed till I get all the bugs worked out just in case I need to hack up the wiring again!
thanks
edit: the setup if it helps
- D16A6 with 200, xxx km's into a Civic CX hatch using the fourthgenhatch.net DPFI to MPFI tutorial
- 4-2-1 headers
- crush bent exhaust
- I replaced the fuel filter, timing belt and water pump when I did the swap, plus the cam, crank and rear main seal
- All the connections are soldered and heat shrinked
The car runs great and has good power (I was driving with the D15B2 for more than a year!) but the only problem is a grind going into 5th gear (GM synchromesh fixed it.. for now) and the slow rev dropping between gears.
Yes, the wiring looks like ****, I'm leaving it exposed till I get all the bugs worked out just in case I need to hack up the wiring again!
Last edited by nicholasmak; 01-18-2009 at 09:24 PM.
#2
Honda-Tech Member
Join Date: Mar 2007
Location: chicago, il, usa
Posts: 302
Likes: 0
Received 0 Likes
on
0 Posts
Re: Throttle problem after DPFI to MPFI swap
i would make sure that the dashpot on the throttle body isnt adjusted too far. the purpose of it is to slow down the rpm drop when shifting, it works off a vacuum source from the manifold. theres a tab on it that almost or maybe even touches the throttle valve. try disconnecting it and plugging off the manifold vacuum source and see if it goes away
#5
Junior Member
Thread Starter
Join Date: May 2008
Location: OM NOM NOM
Posts: 45
Likes: 0
Received 0 Likes
on
0 Posts
Re: Throttle problem after DPFI to MPFI swap
So today I finally got around to working on my car (school full time etc etc), I checked for vacuum leaks 4 times (twice when cold, twice when hot) and still nothing. I took off what I believe is the FITV (it was unhooked from when I did the swap) and I have no idea if this could be the problem. The car idles high when cold, but I guess its doing it with the EACV? I'm not too sure how this stuff works. I also disconnected the dashpot and cappped off both ends (the dashpot and manifold vacuum nipple) and the problem is still there! I'm stumped guys!
Is this the FITV?
I opened it up to see if could be adjusted like the ones I saw when I did a search on FITV's, this one just has a spring and a block off sorta cap on one end and a rod (seems to be electronically controlled) to push it open on the other.
Is this the FITV?
I opened it up to see if could be adjusted like the ones I saw when I did a search on FITV's, this one just has a spring and a block off sorta cap on one end and a rod (seems to be electronically controlled) to push it open on the other.
#6
Junior Member
Thread Starter
Join Date: May 2008
Location: OM NOM NOM
Posts: 45
Likes: 0
Received 0 Likes
on
0 Posts
Re: Throttle problem after DPFI to MPFI swap
Ok I just unhooked the purge solenoid cut-off valve vacuum line and capped the manifold and the problem is still there (running out of things to try!). Would a malfunctioning EACV/IACV or whatever cause this? I cleaned it with throttle body cleaner and the motor ran fine when it was still in my CRX. Any way to eliminate it as a possibility? Unplug it when the engine is warm?
#7
Honda-Tech Member
Join Date: Dec 2007
Location: Greenbrier, Tn, United states
Posts: 370
Likes: 0
Received 0 Likes
on
0 Posts
Re: Throttle problem after DPFI to MPFI swap
try loosening the throttle cabe adjuster.. if its too tight then when u let off the gas, the butterfly deal isnt gona close like it should.. itl keep it open slightly
Trending Topics
#8
Honda-Tech Member
Re: Throttle problem after DPFI to MPFI swap
In regards to your picture above. thats not your fitv (fast idle thermal valve). the a6 doesn't even have one. it is a fast idle control solenoid valve and is used to increase the air flow rate for fast idling at extremely low ambient temperatures (when coolant temp is below -14 degree fahrenheit or -10 celsius) and when engine speed is below 1,800 rpms.
#9
Junior Member
Thread Starter
Join Date: May 2008
Location: OM NOM NOM
Posts: 45
Likes: 0
Received 0 Likes
on
0 Posts
Re: Throttle problem after DPFI to MPFI swap
thanks!
#10
Honda-Tech Member
Re: Throttle problem after DPFI to MPFI swap
also, the ficsv is not needed unless you actually see temps that low. and its not going to cause a problem if you remove it. just make sure you plug up the hole in the intake manifold if you leave it off.
Last edited by D16SiHatch; 01-18-2009 at 07:59 PM.
#11
Junior Member
Thread Starter
Join Date: May 2008
Location: OM NOM NOM
Posts: 45
Likes: 0
Received 0 Likes
on
0 Posts
Re: Throttle problem after DPFI to MPFI swap
also maybe once it warms up some part of the tb assembly is getting jambed? does the throttle plate close any faster between when its hot or cold?
In regards to your picture above. thats not your fitv (fast idle thermal valve). the a6 doesn't even have one. it is a fast idle control solenoid valve and is used to increase the air flow rate for fast idling at extremely low ambient temperatures (when coolant temp is below -14 degree fahrenheit or -10 celsius) and when engine speed is below 1,800 rpms.
In regards to your picture above. thats not your fitv (fast idle thermal valve). the a6 doesn't even have one. it is a fast idle control solenoid valve and is used to increase the air flow rate for fast idling at extremely low ambient temperatures (when coolant temp is below -14 degree fahrenheit or -10 celsius) and when engine speed is below 1,800 rpms.
#12
Junior Member
Thread Starter
Join Date: May 2008
Location: OM NOM NOM
Posts: 45
Likes: 0
Received 0 Likes
on
0 Posts
Re: Throttle problem after DPFI to MPFI swap
Ok I just got home from school, I cleaned the throttle body before I drove home and the problem is STILL there. I think the problem is something I must have missed while checking the throttle assembly or probably EACV related. Any thoughts?! I've checked the throttle area over many times so far and I've elimated a bunch of possible problems..
#14
Junior Member
Thread Starter
Join Date: May 2008
Location: OM NOM NOM
Posts: 45
Likes: 0
Received 0 Likes
on
0 Posts
Re: Throttle problem after DPFI to MPFI swap
ok I finally got around to working on my car yesterday, I covered the EACV/IACV hole with tape and the problem is gone! But would the fault be in the valve or something electrical? The wires for the valve were extended for the swap. Any way to test it? I want to narrow it down before I start replacing parts!
#15
Honda-Tech Member
Re: Throttle problem after DPFI to MPFI swap
ok I finally got around to working on my car yesterday, I covered the EACV/IACV hole with tape and the problem is gone! But would the fault be in the valve or something electrical? The wires for the valve were extended for the swap. Any way to test it? I want to narrow it down before I start replacing parts!
to test the iacv, ground the blk/yel wire and hook up +12v to the blu/yel wire. colors may be different since you've extended the wires and such, but i would imagine you should be able to determine which one is ground lol.
#16
Junior Member
Thread Starter
Join Date: May 2008
Location: OM NOM NOM
Posts: 45
Likes: 0
Received 0 Likes
on
0 Posts
Re: Throttle problem after DPFI to MPFI swap
so at this point the only problem is that it is slow to come down to idle?
to test the iacv, ground the blk/yel wire and hook up +12v to the blu/yel wire. colors may be different since you've extended the wires and such, but i would imagine you should be able to determine which one is ground lol.
to test the iacv, ground the blk/yel wire and hook up +12v to the blu/yel wire. colors may be different since you've extended the wires and such, but i would imagine you should be able to determine which one is ground lol.
#17
Junior Member
Thread Starter
Join Date: May 2008
Location: OM NOM NOM
Posts: 45
Likes: 0
Received 0 Likes
on
0 Posts
Re: Throttle problem after DPFI to MPFI swap
UPDATE: I fixed the problem! Turns out the ECU was acting up. I've been trying to figure this out for like 6 months. My boss had a PG7 out of his old Integra laying around, so I swapped it in and it drives like a dream. Feels like it has a bit more power too, possibly because the PG7 maps are different. Thanks to everyone who's helped me out!
Thread
Thread Starter
Forum
Replies
Last Post
88si
Honda Civic / Del Sol (1992 - 2000)
5
02-28-2009 05:27 PM
wes7side5o
Honda Civic / Del Sol (1992 - 2000)
15
03-16-2007 06:47 AM
bumthology
Honda CRX / EF Civic (1988 - 1991)
3
01-13-2006 09:06 AM