Funkspectrum

iTrader: (5)

I checked all the necessary basic stuff ( filters, plugs....etc. ). The bastard is still doing the same ****! I can't figure it out! Could it be a vacuum issue? Under boost the car runs fine but the second I stop and let it idle, it flips out on me. It occasionally holds revs at 3k also. Kinda does the whole cold start thing when it's warm...
I don't understand!

Someone help! I need advice on what to do....

Icemark

TPS??? did you check TPS yet?

DEZERTE

COULD be a vacuum leak. The dieing when stopped especially. Bad intake gaskets can even cause this. --im not positive, just an idea of what else it could be.

rs_1101

low compression or vacuum leak.

Funkspectrum

iTrader: (5)

well...Compression is high....vacuum leak is probably it i think...and I haven't checked the TPS yet. I really don't even know where the TPS is let alone check it!

DerangedHermit

Search time...

Parastie

Do what i do, keep your foot on the gas

Also, have you checked the fuel filters (including the intank filter)?

ra ra rotory

In tank filter? New to me, where is it and how do I replace it?

turbine

iTrader: (1)

pull up the carpet in the back and there will be a little access hatch with 4 screws and an ele connection remove screws and then there will be more screws take thoes out too and remove fule pump assembly and there will be a little sock on the end of the pump

rs_1101

in experience.. worn TPS is usually the culprit like .... 10% of the time. a better symptom of a bad tps is loss of power, or strange surges in power. its pretty easy to test. all you need is a multimeter or if you have safc, just watch the dials.

bad idles seem much more commonly caused by old, broken/brittle vacuum lines.

skatingsamurai

yeah on my TII o had several(rubber) hoses on the back side of engine passenger side. thare are several that are grouped together back there. dont just go ripping them out though..unless you want to take off the UIM which is where the other brittle lines usual are. right near the fuel rails. the obvious ones though are right on the pass. side of block.

(i dont even want to think about a 13rew OR even 3 rotar's rats nest full of vac hose. so consiter yourself lucky if it is a vac leak)

NSBerkland

I dont mean to hijack this thread but while we are on the semi topic of TPS's I dont have a surging idle but it will randomly decide hey I wanna idle at 950 or a few mintues later 1200 or the next minute 400. I have tryed testing the TPS with my volt meter and no matter what outta the 3 hole green plug I get 10.9'ish volts outta both bottom holes no matter how many turns either way. Is this probally a sign that my TPS is just pooched? or am I stupid and not doing something right?

Sith_Lord

( Not trying to hijack either) I got sorta the same problem....Started the other day. I will be driveing along and when I come to a stop the idle will bounce around from 1k to 1500, then down to around 400....then she dies. Is the TPS expensive? and can someone supply a pic of it. Not sure where it is.

Corbit

OH Ya ( not trying to hyjack the thread either ) Wow me too , but really, if you do a search you can learn alot, I did but could'nt find my problem . Also if or when you find the problem please finish your post with the results, there is nothing more frustrating than doing a search to find someone with the same problem and have them not post up on how they fixed it. Good luck , i use to live in Santa Rosa.

Funkspectrum

iTrader: (5)

To all thread hijackers....

I'm glad that there's someone else with a similar problem as mine! So, it's ok that you guys semi-hijacked my thread...

Ok...well...I was going to check the in-tank filter but I decided that I was just going to take the car to Michaels Mazda performance in Rohnert Park. Mike is a good friend of mine. I would do all of the troubleshooting myself but I don't have all that time. I did some minor **** today like change the plug wires....check the idle screw under the intercooler, blah, blah, blah....

Anyway...thanks for all your input

Chuckles

I'll jump on the hijack bandwagon.

I searched a bunch and understand the lights, ohms, and volts TPS adjustments. Now if I could find the damn TPS, I'd be doing great. Blind, trifocals, and old.

On the 10AE, there is so much stuff in the way that unless you know what it looks like you're lost. It looks like from the FSM, the TPS is on the back driver's side of the throttle body. It also says you can check it without removing the intercooler, but must remove to adjust it?? Am I myopic? (sp?)

Can someone post a picture of the TPS and its location for a 87-88 TII?

I'll be your friend for life!

HAILERS

You need to start at square one. Your car needs a tune up, and I don't mean just changing plugs and air filter.

Get a FSM. It's free online.

Set the timing.

Set the TPS.

Set the idle per fsm.

If you really think with good reason, that you have a bad tps....check the tps per the fsm. It's free and online.

Check you bac's operation. You basically do that in conjunction when setting the idle.

HAILERS

The Green Check Connector..........It has a black/white wire. That is a constant battery voltage. It should not change. The other two wires are *taps* from the ECU. When the tps is set to certain conditions, these wires will get a ground signal from the ECU. When the tps is set right, only one of the two wires will have a ground on it. It will be the blue/yellow wire. BUT..you really need two meters to set the tps using the Green Check Connector to monitor when the ground is put on one wire while the other wire loses its ground. Basically forget about using the green check connector for setting the tps using a meter/meters.

It's simpler to make/buy two LED's from Radio Shack for two bucks and installing them in the Green Check Connector and watching them turn on and off as you adjust the tps. This method does not check out the serviceablility (sp?) of the tps. To do that go to the fsm and ohm it out.

AS for setting the tps using a meter, some of us find it much simpler to just tap into the green/red wire at the tps connector or at the ECU and with a fully hot engine, adjust the tps until you see approx 1 vdc on the meter. Done.

On a 87 turboii you'll find the tps attached to the throttle body if you remove the intercooler. It can be adjusted without removing the intercooler by using a LONG common screwdriver and monitoring the two LED's as described above.

Somewhere on this site is a how-to on rigging the two LED's. You have two wires on each LED. Join one wire from each LED together. It's usually a red wire. Put a spade connector on the end of those two joined wires. The spade should be of a size to fit into the Green Check Connector. Then put a spade on each of the two remaining wires of the LED's. So now you have three spade connectors. Put the spade connector that has the two wires joined together into the socket on the Green Check Connectors that has the black/white wire. Then put the other two spade connectors into the remaining two sockets of the Green Check Connector.

Get the engine fully HOT. Then turn just the key to ON. Then turn the tps screw fully counterclockwise to a point where the screw is just about to fall out...but does not. Then slowly turn the tps screw clockwise while watching the two LED's. One light will eventually come on. Keep slowly turning til the second light comes on and then stop. Now turn the screw anti-clockwise til you have but one light on. Your done. If at this point you put a meter on the green/red wire at the TPS connector with the connnector connected, you will see approx 1vdc.

If at any time you are trying to adjust the tps and only one light or no lights come on......most likely the output device in the ECU has been fried though some mishap in the past. That does not mean the tps is shot, only that the drivers for the ground singnal to the green check connector is shot. YOu can still set the tps using a meter taping into the green/red wire of the tps and monitoring the voltage output of the tps and adjusting it to approx one volt.

Much of the above is series four related. I don't mess with series five.

MarkPerez

yeah, it's really easy to make your own 2 light , i'll call it a tps checker. i use 2 side marker socket/bulbs from a 1st gen or a 2ed gen from the junkyard. twist the 2 red wires together and the 2 yellow wires together and to test the bulbs just touch the wires to the battery. the innercooler does not have to be removed to adjust the tps
but if you don't know where the tps is then maybe remove the ic untill you know where. the tps is right in front of the tb it's the only thing with wires coming off the linkage. can't miss it. with the ic in place a really long flat blade screw driver will work.
from the drivers side, right behind the alt. and under the ic it can be seen and adjusted. when adjusting the tps don't push hard with the screw driver that will move the linkage, push soft and turn. i placed the 2 bulb setup up on the ic and used a 2 wire jumper with aligator clips to hook up the 2 bulbs. on the green check connector i did use 2 flat spade 'stak-ons'. i placed those in the 2 lower female spades in the green check connector. reading hailers how-to i'm not to sure if i did the check right though by using the 2 lower connections but i had both bulbs lite. when turning the tps adjustment screw i could hear the tps 'clicking' i'm not sure if the 'clicking' means the tps is history or not. but the engine still surges from 1300 to 1600 rpm's driving the car i can feel the throdle way more even though. under load the engine spins up smooth all the way. no power band type feeling just smooth and even. since adjusting the tps when i roll up to a stop at least the idle doesn't change every time. it used to go from 750 and even and the next time it would be 1100 and surging each stop would be different. i've got to pull the bac and apply 12v to test if it's shot. but it's getting closer and closer. what a bitch i'm telling you all the valves, vacum hoses, all that **** can be over whelming to a noob like me on this t2. i find the problem ,i'll post the cure.

rs_1101

bouncing idle can be caused by vacuum or poorly set/broken tps.. someone once explained exactly how it works.
changing idle.. i have that problem. then i hit the brakes and it drops to 830. it could be stuck throttle plates.

MarkPerez

can you believe it.. got that ******.. i pulled the bac valve and applyed 12v and watched what it did and it wasn't closing all the way. on the valve ends there are 2 allen headed screws . on the smaller allen i used a allen wrench and moved the position of the screw. loose then tighten. enough so the rubber seals. apply 12v to test. it worked for me.

Funkspectrum

iTrader: (5)

Sweet! so much info! Thanks a bunch guys! I'm gonna attempt to check the TPS tomorrow when it's light out. I'll update too!

jdonnell

iTrader: (1)

My idle went high around 1200rpm and wouldn't go lower. When it got hot it would want to die then bounce around eratically. Turned out to be cheap silicone vacuum hose I used when changing my fuel injectors. I had run out of the good stuff (Hose Techniques) and had to get the cheap stuff fast at Autozone. It was all used under the manifold (of course) and it deformed and closed itself shut. Junk hose

FC3Sideways

Check your TID or intake!! i had the worst idle ever and replaced my turbo inlet duct that was cracked . .. tightened all the clamps and it idles PERFECT !!!!!!

Chuckles

Hailers, MarkPerez, rs_1101 - thanks a bunch for taking the time to clarify the TPS, BAC and idle riddle. Hailers, a special cudo on your simple, step-by-step explanation. I appreciate it!