Bad idle, Hesitation under load, black smoke

FRFC3S · 03-31-2008, 06:52 PM

.

J-Rat · 03-31-2008, 07:16 PM

Jesus! Might just want to go ahead and slave in a spare ECU and see what happens.

FRFC3S · 03-31-2008, 07:23 PM

.

Rotary_Rocket_87 · 03-31-2008, 07:28 PM

Check to see if all the electrical connectors are tight under the hood. My car did something very similar to yours cause the TPS and AIT sensors had come unhooked.

FRFC3S · 03-31-2008, 10:33 PM

.

J-Rat · 03-31-2008, 10:49 PM

Actually, you would have to check the voltage after the resistance drop, with the red lead on the proper pole of the sensor and the other lead on a chassis ground.

FRFC3S · 04-01-2008, 01:07 PM

Quote:

Originally Posted by J-Rat

Actually, you would have to check the voltage after the resistance drop, with the red lead on the proper pole of the sensor and the other lead on a chassis ground.

Thank you J-Rat. I will try that and I will try retiming it and get back to you guys. Please post any further ideas.

Ender · 04-01-2008, 01:38 PM

http://www.rotorwiki.com/index.php/TPS_Adjustment
Make sure you use the S5 instructions. Your TPS could be bad, and a reading of '1', with the 1 being all the way to the left of the multimeter screen, means that the resistance is either infinite (meaning no continuity, no connection) or you are using too low of a setting. If it's '1' all the way to the right then you are probably using too high of a setting on the meter and you should turn it down until you get a non-one reading or you are as low as it will read.

FRFC3S · 04-01-2008, 10:00 PM

.

Ender · 04-01-2008, 10:34 PM

I did, it's just that the TPS can be problematic even if it seems to test out ok. I and others have had it happen before.

You may be on to something with vacuum leaks, they're very common and can cause really weird problems. I found the most help from a tool that plugs the intake and has a pressure gauge mounted to it, you can pressurize the intake with the adapter that's on it. I tried a few different methods of finding vacuum leaks and none of them were a fourth as effective as doing it with this tool:
http://boostpro.net/prodtester.html
You'd want one of these two for the best results:
Boost Leak Tester (Gauged)
3" Diameter
With Tire Valve Adapter
$20 + $4.60 shipping

Boost Leak Tester (Gauged)
3" Diameter)
With Male Compressor Coupler
$20 + $4.60 shipping

And here's a DIY option that you can modify to make work for the '7:
http://www.supercar-engineering.com/...T/IntPresTest/

FRFC3S · 04-02-2008, 05:57 PM

.

FRFC3S · 04-02-2008, 06:47 PM

.

FRFC3S · 04-03-2008, 08:32 PM

.

djmtsu · 04-03-2008, 09:29 PM

I am under the impression that if the boost sensor is bad, it would thrown the CEL. Is your light on?

Also, I have never heard of the the boost sensor failing (on its own) on an FC.

Oh, and I don't have that many CEL codes on my S5 emissions removal.

FerociousP · 04-03-2008, 10:17 PM

you can use a n/a ecu... you just drive easy and can't boost... that would be a good way to test the engine lights..

03-31-2008, 06:52 PM	#1
FRFC3S The Newbie Join Date: Mar 2008 iTrader: (1) Posts: 11 Rep Power: 0	Bad idle, Hesitation under load, black smoke . Last edited by FRFC3S; 09-10-2020 at 02:34 AM..

03-31-2008, 07:16 PM	#2
J-Rat Rotary Fan in Training Join Date: Mar 2008 iTrader: (0) Posts: 59 Rep Power: 17	Jesus! Might just want to go ahead and slave in a spare ECU and see what happens. __________________ 1988 10th Anniversary 554 RWHP, 395 RW Torque 10.7 @ 126! owner: www.azrx7.com Engine built by ARIZONA ROTARY ROCKETS www.azrotaryrockets.com

03-31-2008, 07:23 PM	#3
FRFC3S The Newbie Join Date: Mar 2008 iTrader: (1) Posts: 11 Rep Power: 0	. Last edited by FRFC3S; 09-10-2020 at 02:35 AM..

03-31-2008, 07:28 PM	#4
Rotary_Rocket_87 2nd Generation Freak Join Date: Mar 2008 Location: Chuck Vegas, NH iTrader: (0) Posts: 64 Rep Power: 17	Check to see if all the electrical connectors are tight under the hood. My car did something very similar to yours cause the TPS and AIT sensors had come unhooked. __________________ '87 TII- full emissions removal, a/c removed, FPD removed, dual 12" e-fans, Rotary Performance FCD, ACT unsprung 6 puck w/ Xtreme PP, custom open 2.5 inch exhaust, custom clutch pivot ball, K&N cone filter, TB mod, RB downpipe, motor blown 8/7/09 '94 Mazda B4000- POS beater truck, stock "The easiest way to fail is to never try." - Me

03-31-2008, 10:33 PM	#5
FRFC3S The Newbie Join Date: Mar 2008 iTrader: (1) Posts: 11 Rep Power: 0	. Last edited by FRFC3S; 09-10-2020 at 02:35 AM..

03-31-2008, 10:49 PM	#6
J-Rat Rotary Fan in Training Join Date: Mar 2008 iTrader: (0) Posts: 59 Rep Power: 17	Actually, you would have to check the voltage after the resistance drop, with the red lead on the proper pole of the sensor and the other lead on a chassis ground. __________________ 1988 10th Anniversary 554 RWHP, 395 RW Torque 10.7 @ 126! owner: www.azrx7.com Engine built by ARIZONA ROTARY ROCKETS www.azrotaryrockets.com

04-01-2008, 10:00 PM	#9
FRFC3S The Newbie Join Date: Mar 2008 iTrader: (1) Posts: 11 Rep Power: 0	. Last edited by FRFC3S; 09-10-2020 at 02:35 AM..

04-02-2008, 05:57 PM	#11
FRFC3S The Newbie Join Date: Mar 2008 iTrader: (1) Posts: 11 Rep Power: 0	. Last edited by FRFC3S; 09-10-2020 at 02:35 AM..

04-02-2008, 06:47 PM	#12
FRFC3S The Newbie Join Date: Mar 2008 iTrader: (1) Posts: 11 Rep Power: 0	. Last edited by FRFC3S; 09-10-2020 at 02:35 AM..

04-03-2008, 08:32 PM	#13
FRFC3S The Newbie Join Date: Mar 2008 iTrader: (1) Posts: 11 Rep Power: 0	. Last edited by FRFC3S; 09-10-2020 at 02:35 AM..

04-03-2008, 09:29 PM	#14
djmtsu My minds tellin' me no... Join Date: Feb 2008 Location: Murfreesboro, TN iTrader: (10) Posts: 4,043 Rep Power: 21	I am under the impression that if the boost sensor is bad, it would thrown the CEL. Is your light on? Also, I have never heard of the the boost sensor failing (on its own) on an FC. Oh, and I don't have that many CEL codes on my S5 emissions removal. __________________ 1976 Mazda Cosmo RX-5 1976 Mazda Cosmo RX-5 2003 Toyota Tundra TRD 2015 Toyota 4Runner SR5

04-03-2008, 10:17 PM	#15
FerociousP I-had-a-bad-experience... Join Date: Feb 2008 Location: M'boro iTrader: (2) Posts: 1,046 Rep Power: 18	you can use a n/a ecu... you just drive easy and can't boost... that would be a good way to test the engine lights..