beaten by a 1uz

taka21

taka21

New Member
Feb 16, 2008
363
0
0
washington dc
i think ive tried everything folks and to no avail
my summer project is still kicking my butt
i have replaced cats, ecu's, maf's and vacum hoses
and i still have the same issue of the damn thing will not rev past 4k and is kicking black smoke from running extremely rich, i just have a few final questions before i totally give up , as this project has me to the point where i am doubting myself and what little mechanical skill i thought i had gained.
1 can the idle air control valve be completely removed without harming functionality of the motor?
2 if the fuel return line is too large would that cause a rich condition in the engine
3 what would cause the maf and iacv to not communicate with the ecu?
im officially stumped with this project daily driver please anyone, i really need a direction to go in
thanks
 
Chambers

Chambers

Now you know
Sep 9, 2007
981
0
0
34
Baltimore County, Maryland
1. The idle controller cannot be removed from the engine, otherwise it will not hold a idle.

2. The fuel return line should not have any ill effects on running rich/ lean.

3. There may be a broke wire/ bad ground between them.

Make sure your AFM is pointing in the correct direction.

Does the engine break up at all during revs untill it hits 4k? When it hits 4K does it just flat line there?

Can you produce any video of the problem? That would greatly help diagnose the problem.
 
Chambers

Chambers

Now you know
Sep 9, 2007
981
0
0
34
Baltimore County, Maryland
Ok, seems like the isc is not working. Go to local junk yards and look for a LS400 or SC400, I would recomemd Crazyrays, they are local and have plenty of donor LS400, there is one in Mt. Airy and Jessup, those would be closest to you. My 1UZ sounded similer, it had a idle surge, I took a pair of pliers and pinched the ISC supply pipe, and the idle leveled out. I pulled a isc from a LS400 at crazyrays in Edgewood.

As for revving, check all your grounds, all your spark plug leads, even pull your spark plugs and check the gap on them. Check your timing as well, and check your cap and rotors, if they look ragged then I'd replace them. Also make sure your ignighters are grounded properly. Good luck.
 
Chambers

Chambers

Now you know
Sep 9, 2007
981
0
0
34
Baltimore County, Maryland
That screams AFM to me, I just recently helped out a local 7M-GTE guy whose car would not rev. When we gave it throttle it would just flat line and bog and wouldn't really go more than 2k rpms, but we could "feather" the throttle and achive 3-4K rpms. We tried everything, swapped ECU, swapped TPS, even swapped AFM bodies and electronics and it still wouldn't run. It turned out to be the AFM on backwards, thats why I brought it up before.

You say you have a Blaster 2 Coil installed, I say find a factory one and swap it back. I don't see the aftermarket piece communicating with the ECU properly, so that may be an issue. Also, it may seem simple and stupid but check all your plug wires, make sure they are going to the correct cylinder/ distributor cap location. The more things you can rule out the better chances you have at finding the issue.

The AFM you have on that engine is different than any I have seen. After a quick search its seems like you have a very late model 1UZ without VVTi, and that should be the AFM for that engine, but trying to find one to swap out if it comes to that may prove difficult.

It also sound like your power steering pump is low on fluid, not your top priority right now but something to consider.
 
taka21

taka21

New Member
Feb 16, 2008
363
0
0
washington dc
ok i re connected the original coils, the plug wires are all correct and the distributor caps and rotors are in good shape.
re filled the power steering lol
now would you happen to know where all the major grounds are cause i can only find two and know theres more.
all i found was the small one on the back of the motor that bolts to the firewall and the battery ground to the block
also where did you ground all your ecu wiring stuff to
thanks
also the maf is new and the arrow is pointing in the direction of the flow of air
 
taka21

taka21

New Member
Feb 16, 2008
363
0
0
washington dc
found the issue
it was in the wiring
the major sensors were not getting power now that they have power the car idles muuuuuuuuuuuuuuuuuuch smoother and the power delivery is smooth as well
i still have some smaller issues to sort out now since that issue is taken care of.
thank you all for all your help in figuring this out.
just in case anyone is wondering the current issues are that the tach needs to be calibrated, the tps needs to be reset, oil pressure guage needs to be hooked up and i need to figure out why the speedo is not registering anymore
 
Chambers

Chambers

Now you know
Sep 9, 2007
981
0
0
34
Baltimore County, Maryland
Good to hear you got it going.

I have seen one guy on here use a mid to late 80's Celica tach motor. He swapped the stock Supra 6 cyl tach motor assembly for the Celica 4 cyl tach mtor assembly and it reads correct. I have my factory tach wired and it works, I just put a old school AutoMeter tach for now.

I found the TPS a PITA! To set via the factory repair manual with a ohm meter, but it can be done.

When I did mine, I replaced the 1UZ "dummy light" oil pressure sensor with the Supra Oil Pressure Sensor and swapped plug ends to get it to work.

The speeo cable is in two parts, the longer of the two goes from the dash down near the trans on the pass side of the car, then there is a shorter peice, make sure they are all connected.

Good luck!
 
taka21

taka21

New Member
Feb 16, 2008
363
0
0
washington dc
the secondary speedo cable snaped on the inside
do you have the specs for setting the tps and what pins to clip to?

also did you notice your steering being especiallly twichy or overly responsive after the swap??
 
Chambers

Chambers

Now you know
Sep 9, 2007
981
0
0
34
Baltimore County, Maryland
taka21;1633535 said:
the secondary speedo cable snaped on the inside
do you have the specs for setting the tps and what pins to clip to?

also did you notice your steering being especiallly twichy or overly responsive after the swap??
Click to expand...

Haha, I wouldnt know about the steering as I went with a Mustang II manual steering rack from Flaming Rivers. But I can imagine the power steering pump for the SC400 has different valving/ line pressure so that may be why its the way it is.

I can see what I can find on the TPS, I had a print of the manual on how to go about it.
 
taka21

taka21

New Member
Feb 16, 2008
363
0
0
washington dc
Chambers;1633541 said:
Haha, I wouldnt know about the steering as I went with a Mustang II manual steering rack from Flaming Rivers. But I can imagine the power steering pump for the SC400 has different valving/ line pressure so that may be why its the way it is.

I can see what I can find on the TPS, I had a print of the manual on how to go about it.
Click to expand...

thanks man
how is that manual steering rack working out for you ?
 
You must log in or register to reply here.
Top Bottom