hi, on my 87 TII i have done a few mods, i have had it running but it wouldnt hold a steady idle (very eratic) now i got done fixing a blown fuel line and it wont idle at all. It will start run some were up around 1700 to 2200 then it dies, i can keep it running if i stay in the throdle, but again it will not idle. I have a list of things i have been checking off to try and figure out what it is and things that i think it could be. I have narowed it down to these things i think: i have done a banjo bolt/pulsation damper sawp w/ a walbro 225lph pump, i have both of the nipples that go to the intercooler capped off, and i have my AFM almost directly atached to the turbocharger with a adaptor fiting. I was wondering if some one had problems like this and any ideas i could try. thank you.

 

does anyone have any ideas?

 

I had the same problem, it was the AFM.

 

it also has a masive stumble at 3500-4000 rpm "rtec 1.8", i was also thinking this could be a symptom of what is wrong. i was thinking that the it could posibley be the AFM, because it is atatched almost directly to the turbocharger. i wonderd if because its too close to the turbo.

 

incase AFM is shot, would a NA afm work. i have a s5 NA that i was thinking about fabing up on the harness.

 

a stumble around 3800RPM is commonly fixed by regrounding some stuff including the ECU. may or may not be the cause of that particular issue.

 

i would like to know more about these grounding problems, i have a rtec7 1.8 ecu upgrade so the secondarys come on at 3500rpm.

 

search for '3800 rpm hesitation', there are writeups on how to improve your grounds

 

I ahve the same problem too. only when i hold the gas at 3k rpm for about 30 secs it idles on its own afterwords at 1.5. is there any solution to this?

 

i can give the re-grounding a shot, but i dont know what wires to ground. i know what the wires names are, "Extract the ground wires 3A, 3G and 2R from the ECU plugs" as taken from hailers thred, but i dont know how to figure out what wires these are in the plugs.

 

from the FSM

 

what is the FSM?

 

Factory
Service
Manual

...

 

I've had a similar problem and fixed it, but in your case you should give us the error codes, when they occur if any. You can also check the AFM using the FSM.
Tell us what's about after.

 

well i checked my leading plugs on a whim, and guess what, they dont work. so i'm getting some new ones tomarow and see what happens.

 

well i tryed new leading plugs and it didnt change anything. O well, back to square one.

 

how do you mean 'they don't work'? no spark from them at all? because if that's the case you maybe have a bad coil pack.

 

maybe but they did have a bit of ash build up. I also checked them buy pulling the inj fues under the hood, i dont know if that would cut the spark too, i also dont know how you would you check the coil ether? i dont have a FSM so i still dont have any way of finding the correct pins, sorry.

 

you can check for spark the conventional way I believe, arc it to the engine block.

with ash or carbon build up you might do the water treatment and or seafoam. and probably replace your plugs if you haven't already.

 

i got new leadings, i checked for spark through the plugs but i havent just watched the boots arc yet, gotta try that.

 

it kindof idles now because i capped off the bov, but now i cant run any boost. the coils spark like mad, they work good XD.

 

Check your injector resistors also bad resistors can cause hes at transition when the secondaries kick on trust me I'm not saying thats the prob just check it out . It was my problem figured it out after doing all the hes fix's .

Here is a link on what plugs at the ecu are grounds .

http://mazdarx7.iougs.com/faqdiagnosing.shtml

 

how would i check the resistors and i'm also not sure i know were they are? pix any one?

 

The resistors are a silver type box bolted to the wheel well on the pasenger side underneath where the air box would be they have a big yellow plug . Just take it off the car and test it with a volt meter just use like 1k ohms just to see if they are even working . Test from one end of the white block to the other



There will be little rubber covers over the wire connection to the white block on the left as shown by the left arrow . Put the black neg end of the meter on the right side arrow in the pic there will be a metal tab that comes out that side and the red on each wire going intow the white blocks on the left side while keeping the black on the metal tab on the right of the pic .



meter should move for each wire if it doesnt you have a bad resistor

 

i'll give both of those a try tomarow, cuz i dont think i'll have time today. i drove it home from the shop (10miles) it was fun to say the least, engine braking was the best because of the almost constant back fires, lol.