ITB's on an my mr2

rsfire · 04-23-2009, 09:03 PM

Hey, i'm planning on putting some itb's on my mr2. I've got a normal 16valve redhat (bigport engine after the bluetop) 4age in my car. I have heard that i need a new computer for this, but the person I bought it from said that it worked on his stock ecu.
Has anyone done this before? Can I just bolt it straight up, or do i have to modify anything? Will my stock ecu work, and what about the plugs that go into the air flow meter, and throttle position sensor? And how would it affect my low end power not having the tvis any more?

Sorry this is a double post, my bro and i use the same account and i didn't know he already posted. lol

Thanks

Here's some pics of my itb setup

Jackstand Queen · 04-24-2009, 11:41 PM

In the early 85 thru 87 years, Distributor magnetic pickups had 4 distinct lobes. The 02 sensors in these cars had one wire.

From 88 to 89, the magnetic pickup inside the distributor had about ten or so points on it (lobes). The o2 sensors on these year models had 4 wires going to the O2 sensor.

While I have not experimented with changing older with newer distributors and ECU's . . . offhand I'd say that the variances described earlier are sufficient to keep the ECU's, Distributors, and O2 sensors matched up. You could move a complete set, forwards or backwards in year model groups. But I wouldn't mix them up.

By the way, that is a very nice looking Piece of Work you have in that ITB setup. Very Nice.

rsfire · 05-01-2009, 02:22 PM

This is what it's lookin like so far:

I'm having some problems with my tps though. I have the same tps as the 20valve on them right now. When it's plugged in, it has a fairly bad and uneven idle. It sounds like 2 of the cylinders are either trying to fire early or have more air in them than the other 2 when they do fire, i'm not sure which, but either way it doesn't sound very good. When I rev it up, it goes up to about 3k, then drops to 2k, revs back up to 3 and drops again and it does that same thing for as long as i have the gas held open. If I unplug my tps, it idles evenly and it revs up higher and normally without doing all that. Oh, and sometimes it backfires out of the intake too...
Does anyone have any ideas what could be causing this?
I've already posted on mr2oc and figured i'd see if anyone here has any help..
Thanks

Jackstand Queen · 05-01-2009, 07:52 PM

There's a trick to swapping TPS's over from one TB to another.

There is a piece that bolts down underneath the where the TPS mounts onto. It has two armatures, and looks like a deformed wingnut.

O.K. the orientation of the armatures varies from N.A. TB to SC TB. So I suspect yours may not be correct for the TPS you are using. Since your ECU defines which TPS you must use, you've got to find, or make correctly oriented armatures. Or it could be you just installed your TPS in the wrong relation to the armatures. That's very easy to do.

Using an Ohm meter, feeler gauge . . . you can change armatures, or reorientate, until it starts giving the desired readings.

rsfire · 05-03-2009, 06:04 PM

Ya, the itb's didn't have the armature things at first. I took the one from the tvis set up and it seems to be moving the tps correctly. Though the tps is the one from a 20v because it has to spin the opposite direction of the 16v tps. I was told all i need to do is reverse two of the wires and it'll work. though i really dont think my problem is directly related to that.

I checked the voltage in my ecu from the pins from the tps. I get a normal reading at 0 throttle, but at full throttle it doesn't move at all. But it seemed if i leave the voltmeter in the voltage will slowly rise by itself. I'm wondering if the ecu is fried?

Jackstand Queen · 05-03-2009, 06:32 PM

Yeah, ECU's do go bad. Sometimes its very subtle, or intermittant kind of a running problem. Check the codes, and see if its error codes are B.S. (wrong).

TPS's go bad more frequently than ECU's. So, I'd replace, or focus on the TPS testing unplugged from the ECU first.

04-23-2009, 09:03 PM	#1 (permalink)
rsfire No Skills Join Date: Aug 2008 Posts: 41 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	ITB's on an my mr2 Hey, i'm planning on putting some itb's on my mr2. I've got a normal 16valve redhat (bigport engine after the bluetop) 4age in my car. I have heard that i need a new computer for this, but the person I bought it from said that it worked on his stock ecu. Has anyone done this before? Can I just bolt it straight up, or do i have to modify anything? Will my stock ecu work, and what about the plugs that go into the air flow meter, and throttle position sensor? And how would it affect my low end power not having the tvis any more? Sorry this is a double post, my bro and i use the same account and i didn't know he already posted. lol Thanks Here's some pics of my itb setup Last edited by rsfire; 04-23-2009 at 09:23 PM.

04-24-2009, 11:41 PM	#2 (permalink)
Jackstand Queen Cage Fighter Join Date: May 2008 Posts: 677 Thanks: 52 Thanked 56 Times in 53 Posts iTrader Rating: (1/100% )	changes in ECU etc. in later years In the early 85 thru 87 years, Distributor magnetic pickups had 4 distinct lobes. The 02 sensors in these cars had one wire. From 88 to 89, the magnetic pickup inside the distributor had about ten or so points on it (lobes). The o2 sensors on these year models had 4 wires going to the O2 sensor. While I have not experimented with changing older with newer distributors and ECU's . . . offhand I'd say that the variances described earlier are sufficient to keep the ECU's, Distributors, and O2 sensors matched up. You could move a complete set, forwards or backwards in year model groups. But I wouldn't mix them up. By the way, that is a very nice looking Piece of Work you have in that ITB setup. Very Nice.

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05-01-2009, 02:22 PM	#3 (permalink)
rsfire No Skills Join Date: Aug 2008 Posts: 41 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	This is what it's lookin like so far: I'm having some problems with my tps though. I have the same tps as the 20valve on them right now. When it's plugged in, it has a fairly bad and uneven idle. It sounds like 2 of the cylinders are either trying to fire early or have more air in them than the other 2 when they do fire, i'm not sure which, but either way it doesn't sound very good. When I rev it up, it goes up to about 3k, then drops to 2k, revs back up to 3 and drops again and it does that same thing for as long as i have the gas held open. If I unplug my tps, it idles evenly and it revs up higher and normally without doing all that. Oh, and sometimes it backfires out of the intake too... Does anyone have any ideas what could be causing this? I've already posted on mr2oc and figured i'd see if anyone here has any help.. Thanks

05-01-2009, 07:52 PM	#4 (permalink)
Jackstand Queen Cage Fighter Join Date: May 2008 Posts: 677 Thanks: 52 Thanked 56 Times in 53 Posts iTrader Rating: (1/100% )	There's a trick to swapping TPS's over from one TB to another. There is a piece that bolts down underneath the where the TPS mounts onto. It has two armatures, and looks like a deformed wingnut. O.K. the orientation of the armatures varies from N.A. TB to SC TB. So I suspect yours may not be correct for the TPS you are using. Since your ECU defines which TPS you must use, you've got to find, or make correctly oriented armatures. Or it could be you just installed your TPS in the wrong relation to the armatures. That's very easy to do. Using an Ohm meter, feeler gauge . . . you can change armatures, or reorientate, until it starts giving the desired readings.

05-03-2009, 06:04 PM	#5 (permalink)
rsfire No Skills Join Date: Aug 2008 Posts: 41 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	Ya, the itb's didn't have the armature things at first. I took the one from the tvis set up and it seems to be moving the tps correctly. Though the tps is the one from a 20v because it has to spin the opposite direction of the 16v tps. I was told all i need to do is reverse two of the wires and it'll work. though i really dont think my problem is directly related to that. I checked the voltage in my ecu from the pins from the tps. I get a normal reading at 0 throttle, but at full throttle it doesn't move at all. But it seemed if i leave the voltmeter in the voltage will slowly rise by itself. I'm wondering if the ecu is fried?

05-03-2009, 06:32 PM	#6 (permalink)
Jackstand Queen Cage Fighter Join Date: May 2008 Posts: 677 Thanks: 52 Thanked 56 Times in 53 Posts iTrader Rating: (1/100% )	Yeah, ECU's do go bad. Sometimes its very subtle, or intermittant kind of a running problem. Check the codes, and see if its error codes are B.S. (wrong). TPS's go bad more frequently than ECU's. So, I'd replace, or focus on the TPS testing unplugged from the ECU first.