my set-up
 

i know you guys are probally sick of seeing me start threads, but here is another.

http://img85.imageshack.us/img85/3914/img0474xs0.jpg

sleeper intercooler? :rly:

http://img85.imageshack.us/img85/8814/img0477ys3.jpg

details in sig. also open downpipe, and AEM wideband. i will summerize my problems again to see if anyone has any input. had the 310s in, ran ok, just crazy rich. 12.5-13 cruise. as soon as you lean into the throttle, peged out 10:1. put the stock injectors bad in, barley runs. doesnt want to idle unless the afm screw is all the way in, then stalls alot. anything more than 1/4 throttle and it starts missing and sputtering. but i think i found atleast one reason it sucking. the ECU plugs have a couple of coroded wires, and atleast 1 wire is broke, a blue wire IIRC. i will splice in some new plugs and see if it helps. and if not, try a new AFM and injectors. i opened the ecu, everything looked good inside.

interesting heatshield

I just threw away two license plates. I think they belonged to an old roommate.

bondo that crack in the bumper its already primered :gay:
and are you using a saab intercooler?
(nvm, saw it was a probe)
should you still wrap the lines around the turbo? because nothing is protecting the lines behind it:dunno:
whoa and that isn't a piece of pvc on the hotside pipes is it?

aw, it's so cute, tiny intercooler and tiny turbo.


9,725 POST! oh shnap! I have no life.

Does your car have a rattle can spray job? Pics if so.

its not rattle can, its actually sprayed satin black. and there is no pvc anywhere, but they are some couplers for pvc pipe from home depot. i only have 400-500 in the whole setup too.

so does it idle? it doesn't seem like the idle valve has much of an air source :gay:

a little low, but not bad. i still need to get something better for that

fixed the IAC hose, idles better now. and spliced in a new ECU plug to replace the fuged up one. it helped a ton, still studders some. going to put in a rx7 AFM this weekend. i go 6 clicks counter clockwise on the clock spring for stock injectors, right? how many clicks which way for 310s? just want to be sure.

it should be in the faq

hey how does that bov work for you i have the same one but haven't heart it yet?

negative ghost rider

and the BOV works fine. just an ebay knock off, its a couple years old now. i was usuing it on my old probe too. everyone in the area knows your turbo when it goes off

oh, well i thought it was in the faq at one time, as for the clicks just go trial and error, i've heard goin 5 for a starting point and then from there fine tune it

there's no set point

iirc i was 3 clicks with the rx7 afm with 305s. 7-8 with 230s.

10-4 man. i got a wideband, i will figure it out

i think my car hates me. put in the rx7 afm, and tried another set up stock injectors. the AFRs are all over the place, it will just randomly go full rich, bog, studder, and so on. i will try the 310s again with only 3 clicks on the afm and see if it helps. could my ECU be fucking up?

nice on the bov.. i wanted one that would be really loud.haha but still perform good i want to upgrade to the hks ssq one hope fully when i get my car turbo.

ok, i have now decided that my car does in fact hate me. 310cc injectors, rx7 afm set at 3 clicks looser. and the car is still running like crap. pig rich at idle, started the car with the afm cover off, at idle its almost halfway open. i dont know what the deal is. i am thinking about just selling the FMU and AFM and going megasquirt. there is no reason the car should be running as bad as it is

Do it.

or put the stock afm back on. no reason you cant run 305s with it.

cause and point, back to back dyno runs with 305cc injectors and the RX7 AFM and OEM AFM.

oem won.


https://www.miataturbo.net/~web1_bra...rx7_vs_oem.jpg

i know there souldnt be a reason that i cant run 310s on the stock afm, but it does run like crap and rich as hell too

everytime i touch the car, it gets worse. just put the stock afm back in with the 305s, its basically not drivable. studdering, super rich, boging and so on. there is no reason the car sould be running the way it is. i am going to go over the wiring harness to see if there is any damage.

you = teh fail.

you got a wideband, what are the AFRs at idle?

drill out the cap on the OEM AFM to access the idle-mixture screw. back it out about a full turn counter-clockwise, should get you pretty close.

back to basics here. did you check all the wires and plugs? I had a problem like this about 2 years ago, and solved it when I found the wires were breaking apart internally. I replaced the wires and plugs and that bog went away. That could be half your problem. Im willing to bet you have multiple problems here which are making your issues harder to figure out.

toss the origninal AFM in, new plugs and wires, and see what happens. that way you will avoid dealing with a potentially messed up AFM on top of the other problems. How about your fuel pressure reg? Did you check that?

what am i missing here?:
too much fuel being delivered
poor ignition

Check:
Fuel pressure reg for proper pressure and functionality
your injector setup with respect to duration

What I would do:
put the original AFM on (to limit variables)
Put the original injectors in (to limit variables)
Check the fuel pressure
Check the injector durration

This should yield some answer, most likely a problem with your tunning. Tune the sucker, then one by one add your parts back on. Pretty time consuming, but i think that approach would solve it.

Braineak, what do you think?

fuel pressure is exactly where it sould be, have tried the stock afm again. and 2 sets of stock injectors. plugs and wires are brand new NGK peices. i will clean off the plugs to see if it helps any. i have been messing with the screw on the afm for idle. several turns of the screw would only adjust it from 10:1 to about 11.3:1.

Do I understand correctly here- your idle is sucking and when you put your foot into it, the car bogs? Its unlikely you have defective plugs or wires. but testing them and double checking the gap may be worth it. Also- your coil pack may be going bad, leading to issues with your ignition. Your AFM may be a dud for what your doing. hmmm... after checking your coilpack and wire/plug assembly, your next course of action as i see it is to try a different AFM to see if a different unit may get you the mixture your looking for. OH- I have not heard of it, but considering the fuel pump for a spike may be an issue. usually when a car 'bogs', meaning when you step into it, you have an over rich mixture. normally that means your not igniting the air fuel mixture, or their is too much fuel. make the distinction between those two possibilities. it sounds like you are supplying the mixture with a sufficient spark, but youll have to check the gap and ignition coils now to know for sure. after that im betting on the likelyhood that there is just too much fuel- this leads us to the fuel pump, fuel pressure reg, and injectors. I have absolutely no experiance with compression problems, but if you do not have sufficient compression, then there is the possibility that your car would bog also.

check:
ignition coils/pack
spark plug gap
compression

then:
fuel system and associated components

what ratio are you looking for from the AFM?

i have tried other injectors and AFMs, none helped. car ran fine pre-turbo. when i turboed it, i put in new plugs and wires. the car already has a 255 fuel pump in it. its running rich, spark isnt the problem. its just sucks through gas. its not a mechanical problem, its and electrical/sensor problem somewhere

Doesn't the 255 over power the stock fuel pressure regulator thus making it uncontrollably rich. Thus the reason why people go for the 190 lph. Maybe that was only under power though, i'm not the one that would know off hand.

no, the 255 does in fact overwhelm the oem fpr. so it's always rich. like 45psi at idle vs. 35psi.

acording to my fuel pressure guage, idle is 36psi and 0vac is 45psi. i have had the 255 in for a long time, never had a rich problem when i was N/A

beats me then.

I'd check the voltage on your narrowband o2 sensor feeding the ecu (unless you are using NB sim from your WB to feed your ecu that is). It could be a dying/dead NB sensor.

i replaced it also with a new one, no difference

o2 sensor?

Do a pressure leak down test with your piping and intercooler. Random chance you caould have a boost leak cauz your getting fuel but no air to mix with.

boost guage holds nice and steady at 9psi, and idle vac is nice and steddy

For got to ask but are you running a piggyback or just the FMU?

just the fmu, base timing is set to 8 btdc

looiney may be right with the intercooler thing. even if your boost gauge reads 9, your intake may be recieving a bit less.

his gauge is reading off the manifold, so he'll see exactly what the engine sees.

you gotta have a vacuum leak of sorts thats causing the engine to run so rich. the ecu think it's getting X amount of air, but infact it doesn't so you go rich and runs like crap.

what's your vacuum at idle?

about 19in

If there were a bad leak, it should be lean at idle. 19 sounds dead on for idle.

Did you fix that blue wire going to the ECU? IIRC thats a O2 sensor signal wire. If that was not fixed properly, the ECU will go nutzzzzz. Do you have a CEL? Run the code?

i have replaced the damage ECU plug, no chang. no CEL right now. i will run the codes anyway tomorow

put in the stock injectors, new spark plugs, another new o2 sensor, and another ECU. helped some, but it stil randomly bogs and studders, and most of the time has a really rich cruise and randomly will go real rich

Talk about a real mystery. Reading thru the post, you are running rich and ignition stuff checks out okay, right? So running rich:

1) too high fuel pressure - you said pressures were okay so fuel pump/FMU seems to be working okay

2) bad injector (locking open/etc...) - you tried multiple sets so unlikely

3) bad AFM- again, you tried multiple sets with the stock injectors so unlikely



Assuming that your fuel pump, FMU, injectors, and AFM are all okay based on the above, there are only two other sensor that change fueling (aside from the gas pedal...haha) for the 1.6L:

1) o2 sensor - Since you changed sensors as well, is it possible you have a bad connection that is intermittently grounding out? Also, the stock ecu does not use the o2 sensor on a cold start until the car warms up so are your cold starts fine?

2) thermosensor at the back of the head - Again, a bad connection that grounds out the sensor intermittently would tell your ecu that the engine is really cold and dump in fuel.

For both, with a multimeter, you could find the ecu pin and test the readings.
My two cents. Interested to see what the final issue is.

you know what. i have no CEL, but i do remeber getting a thermosensor code before. i just went outside and ran the codes (eninge is completly cold) and i am getting NO codes. the temp guage works fine. but my tach and water temp guage are really jumpy ever sence i put in the MMR solid motor mounts in several months ago (well before the turbo). a new coolant temp sensor is only $15 for a new one, i might just replace it.

Make sure you get the right one. Your dash gauge can be fine even if the ecu sensor is broken as they are two separate sensors so a normal dash reading means nothing.

There are three thermosensors in the miata. One on top of the thermostat housing for the fans, one small spade connector at the back of the head for the dash gauge, and one green connector on the back of the head that feeds the ECU. Make sure it is the green one in the attached pic.

i have replace the one on top of the thermostat before, so that should be ok. i still have no idea why it will just studder for no reason

out of curiousity does this studder effect the idle on the guage? does it feel like the car is tripping on itself, then goes back to normal?

Get some contact cleaner and clean all your sensor leads, that couldn't hurt either.

the studder happens when your on the gas. it will do it at partial throttle and also at WOT and is completly random. idle speed and afr is also completly random

not trying to rag... but that engine bay needs some TLC :) looks like you'd get extremely dirty everytime you touch your engine bay

Ok, Dumbass question from the newbie: Since you are running an afm but no recirculation from the BOV, will it not run rich when the bov opens? And I see you have a breather on the valve cover, but still a PCV valve hooked up. Could the PCV valve leak?

i thought a blow off valve's only job is to let backpressure off the turbo?

the BOV only matters when you are shifting. i have enough spacers in it to keep it closed at idle. pcv is still hooked up. but a leaking pcv hsa nothing to do with running rich, that would cause a whole other set of problems

did you ever get this thing straightened out bryan?

some, but not all the way. i got stock injectors and AFM in. the super rich condition is gone. but the random bog and studder is still there. it will happen at partial throttle and at WOT also

you have an o2 clamp or aftermarket ecu?