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ITS STARTS!..then dies : (

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Old 08-24-07, 05:51 PM
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Exclamation ITS STARTS!..then dies : (

alright so to anyone who has been following. been going threw hell trying to get this wiring set up right for my turbo vert. (88 vert, 87 tII) im using the tII harness with the alt. and sensor wires spliced in. heres the the problem!

i got the car cranking and then it almost wanted to start but it just diddnt seems to want to. after it would stop cranking some smoke would come out of the exhaust. going to asume its oil and gas. i checked to see if i had power from the fuel pump via the bridged connector. have the flow. then i checked for spark. have that. so after i kinda almost got it started i decided to jump start the bitch. first time was a no go. i got a push down the street (yaaaay roller coaster) then tried in 3rd. kinda got a nudge but then would dies once i put the clutch back in. if i just let it out it would keep the engine going, but it wasnt doing anything. a slow gurgle if you will no life. 4th time on the way back from the jump turned it around. it cranked, then started up! then it was rev to make 1k then die. did that like 3 more times. and each time i did it, it got easier to start up. pushed her back in to home base. then decided to check some more things. i bridged the fuel pump, started, went a little higher. then died. i pushed open the AFM manualy almost all the way. started to about 2.5k then died. then i decided to spray some starter fluid. that seemed to have the best result. it went up strong to about almost 3k for a tad bit longer then stoped. has some spray consistant spirts of it as it started to see if it would provide fuel to keep it goin and no good. all of the mentioned start ups never lasted lasted for more then 2 sec.s

-are there any vac lines that can be rearanged on the UIM to cause this?
-electrical gremlins?
-i took the little gizmo (some check valve) that intercepts the TMIC to the BAC off and deadended the lines becuase i snapped one of the nipples off. i diddnt touch the LIM but i checked the tightness of the UIM so it should be air tight. all hoses are snug from the TID to throttle body.
-is there a way to check to manualy check to see if the injectors are opening AFTER start up?
calling hailers, lo l
Old 08-24-07, 06:35 PM
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oh and yes, i found like a bazzilion threads on this, but it seems that mine might be unique in some way.


well! it seems as though unplugging the afm has an effect. i read in another thread that if you unplug the afm and it works better without that its most likelyl the AFM? well it DEF. worked better without the afm. i started up up, and it went straight to a slolid 2k for at least 3 seconds. im absolutely 100% sure it was an improvement. but i tried it it both turbo and NA AFMs and i got the same results?? each afm i had in, had a much more negative effect on the startup/idle.

are the AFMs prone to water damage? becuase i left one of them in the rain for a couple days by accident. and the other fell into some water when i was takin it out. (working outside in the rain, under a tarp)

Last edited by skatingsamurai; 08-24-07 at 06:59 PM.
Old 08-24-07, 08:18 PM
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maybe the injectors are wired up wrong or they are broke (injectors clips)? to me is sounds as if it isnt getting fuel?
Old 08-24-07, 09:12 PM
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Sounds like a LARGE air leak. Maybe the brake booster vacuum line is off at the very back of the throttle body?. The line that's located b/t the firewall and the throttle body. It's to the right of the three/four small vacuum lines on the back.

Or on the back of the turbo inlet duct are two hose. One is small and has a silver check valve on it's end that goes into the TID. The other is larger and is the *blow off valve*.

Sometimes the hose b/t the BAC and the duct that leave the turbo is left off or one end of the hose isn't conneted up.

Or on the intercooler on a series four, there are two openings/hose on the right rear side that need to have hose on the intercooler OR plugged up.

The large hose on the left rear of the intercooler might have it's hose not clamped down. It's the hose/duct that goes to the throttle body elbow to feed the intake.

Since it's firing up, I'd think the primary injectors are on right.

Make sure the turbo inlet duct is not cracked where it mates with the turbo.

Make sure the afm plug is on. Water should not have harmed it and you tried the other afm with the same results so it's probably not the afm itself.

The afm wiring is the same whether na or turbo EM harness, so that's not the problem.

Use the starter fluid sparingly, especially if trying to keep the engine running. It'll make the engine knock. NOt real good thing. I use starter fluid but not to keep an engine running. I kept a lawnmower engine running like that and THAT is what you call KNOCK/RATTLE. Don't want my RX engine doing that.

If there isn't a large hose off, I'd be at a loss. The only way I'd know how to work that problem would be to get a meter out and the page called CONTROL UNIT in the FSM and compare signals at each wire of the ECU plugs with the output stated in the FSM control unit page.

Is the water thermo sensor on the back of the water pump housing connected up? Green two wire plug. If off the ECU defaults to a temp of 176 degrees and won't inject enough fuel DURING the start procedure and the fuel amount won't be right til the engine gets up to operating temps. That's sort of a outside reason it won't start/stay started.
Old 08-24-07, 09:12 PM
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why would you think that? well...ill check to see if the clips are on right...does the ecu change the signals being sent to the injectors somehow after start up??

i can clearly hear a clicking noise right before it shut off when the AFM is NOT hooked up. how do i check to see if my afm(s) is working

im absolutely desperate here. i have to have my running for sun. becuase im leaveing for college...i havent slept in 3 days...im begging for help from you guys, any suggestions here. is there anything at all that i havent clarified? im going to go back under the UIM tommorow morning and check absolutely every single last cm of space to triple check EVERYTHING.

was writing this wile hailers was posting...once again, thanks
Old 08-24-07, 09:14 PM
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And if using a turbo EM harness on a non turbo car, the water temp gauge won't read unless some rewirinng at the X-15 and X-16 plugs is done OR a new wire is somehow run from the sensor to the gauge.

This has NOTHING to do with the engine staying running. It's not ECU related in any way at all. Just some advice in case you notice the water temp gauge isn't working.
Old 08-24-07, 09:27 PM
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[QUOTE=skatingsamurai;7269550]why would you think that? well...ill check to see if the clips are on right...does the ecu change the signals being sent to the injectors somehow after start up??

Think what???????

Anyway, the online TRAINING MANUAL explains how the START CYCLE works. It states that the AFM is NOT used during STARTING. The ECU looks and sees a start signal on pin 3B. It also looks and sees rpm less than 500. It then looks at what the water temp is by looking at the water thermo sensor on the back of the water pump housing.

The water temp from that sensor determines how much fuel is delivered during START. The higher the temp, the less fuel injected during STARTING. So if the plug is off the sensor , the ECU defaults to 176 * BUT the real temp of the engine is stone cold.

After the engine STARTS and gets over 500 rpm, then the ECU uses the signal from the afm.

But seeing as how you tried both afm, I'd doubt that's the problem. By the way, are you using a turbo or non turbo boost/pressure sensor?????? I find using a non turbo sensor on at turbo ECU causes bad idling qualities. The na ECU should START the engine just as well as the turbo afm IF memory serves. I've done that somewhere in my past life.

Testing the afm requires a digital meter and backprobing the wires at the ECU plugs and looking for a value stated in the FSM on the page called CONTROL UNIT.

Other than making sure the wires are going from the afm to the ECU there is no REAL WAY of telling if the afm is good bad. That's my opinion. There is a page in the fsm that checks the afm out but that is severly LACKING in the ability to tell if it's calibrated right or not.

I'm not thinking bad afm myself. The car will start so the afm isn't killing the ref voltage inside the ECU in any way. Nope. Not afm. Unless the plugs off.
Old 08-24-07, 09:31 PM
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sounds like something could be choking the engine. did you maybe accidentally leave a paper towel or somthing in one of the intake runners when (if) it was apart? I wouldn't rule that out.. i had something like that happen once and your symptoms sound identical to when the engine doesn't get air on all the ports.
Old 08-24-07, 09:31 PM
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https://www.rx7club.com/forum/attach...hmentid=150448
Old 08-24-07, 10:30 PM
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alright. i will respond in the morning when im sane and let you know how it goes...

i dont know if this has any baring on anything but just thought i shoot t out there,


1 there are a couple connectors that i diddnt mate down ontop of the tranny, i hooked up everything i could on the front side of the harness.

2 i removed the bypass valve? ontop of the UIM, and bridged the intercooler to the BAC.
Old 08-25-07, 05:50 AM
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removed the bypass valve? ontop of the UIM, and bridged the intercooler to the BAC.********************************************** ************************************************** *************************
That's a mistake. Either put the bypass valve back on or block BOTH the intercooler nipple AND the nipple where the bypass valve connects to the BAC.

In other words that would be a large air leak if it's just bridged like you said. Too much air.
Old 08-25-07, 07:30 AM
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okay, here are my first impressions for having the UIM off this morning. i noticed that the vac lines to the uim may not have been in order. what will this do? that and i noticed a vac line that was disc. from the one solenoid thiger attached to the oil filler neck.i dont know the name of it, but i thought it was some kind of solenoid.

like i mentioned before, i dont know if its worth anything but there ARE some wires not connected down on top of the tranny, and some down on the drivers side of the engine. i one was for ps and one was for ac i believe.

hailers "I'm not thinking bad afm myself. The car will start so the afm isn't killing the ref voltage inside the ECU in any way. Nope. Not afm. Unless the plugs off."

how would you explain why the car wants to stay started for longer WITHOUT the afm plugged in. im going to guess that its likely that since there might be an air leak, the afm is give a signal to the ecu but there is unmetered air getting in which is disrupting the signal??

one more thing. the brake boost line. the one way line between the line and the ?booster? . the arrow SHOULD be point towards the engine correct? that is the direction of air?

Last edited by skatingsamurai; 08-25-07 at 07:57 AM.
Old 08-25-07, 08:39 AM
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im sorry, i just checked , its the EGR valve.
Old 08-25-07, 11:15 AM
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Thumbs down update X-d

okay,

i went into the uim double checked all the vac lines, replaced the egr vac lin. fixed the cracks in the brake booster line, plugged the intercooler- BAC line, and i made certain that all the fittings were tight! nothing!! im going to go and buy a volt meter and im going to go in and pin the ecu so check.

when i started it it was exactly the same as before. oh god it sounds so nice for just that second! then i tried taking the AFM out again and, once again i got much better results. i notice that when AFM is OUT, and i start it. then ill give it some gas, it will choke and then then revs might go back up right before it dies.

so, if i check the ecu it SHOULD tell me if something isnt getting a signal? will i have to start the car? or just have it in the on position...hailers, i remmember you have a walkthrough on how to test the ecu. can you send a link?

i really have a feeling that its something simple that im missing.
Old 08-25-07, 12:14 PM
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You access the ECU and its three plugs.

You put your digiatl metes negative lead on a known ground. A known gnd would be one of the studs that hold the ECU bracket in place.

You leave the plugs attached to the ECU. You don't disconnect any plugs anywhere.

You get your positive meter lead and backprobe each wire at the back of the plugs. You might have to get a sewing needle or such to be able to probe in the back of the wire in the plug and hold the meter positve lead against that needle to get a reading. All readings will be in dcvolts.

The first ones I'd look at would be 2E which would be the output of the afm to the ECU. It'll be close to 4vdc with the key to ON. Your car won't idle so don't pay attention to the pages that give a reading at idle.

If you see close to 4vdc, then go around to the afm and push the vane aft a bit and somehow hold it there. Then look at the meter and see if the value changed. It should have gotten less than 4vdc. Or have someone slowly move it aft then let it return fwd and note the reading going first smaller then back towards 4vdc. If so, it's good most likely.

I'd look at 2B, 2E, 2g,2h,2i,.....3c,3e,3i,3j., 3f,3h.........and 2A for sure. The engine starts so I'd not worry right now about anything to do with the coils or cas.

Just in case.....you leave the plugs attached to the ECU. You count the plugs by reading from Right to Left in a up/down manner, looking at the wire side of the plug while it's attached to the ECU.
Attached Thumbnails ITS STARTS!..then dies : (-ecuplugs.jpg   ITS STARTS!..then dies : (-outputone.jpg   ITS STARTS!..then dies : (-outputtwo.jpg   ITS STARTS!..then dies : (-outputthree.jpg  
Old 08-25-07, 03:28 PM
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sounds good. i have 24 hours almost exactly to fix this, lol. if i dont? well im going to be commuting a half mile every day to school in the snow. hahah

with the brake booster. i checked that the arrow is suppost to be pointed to the engine. but i pulled it out and i try blowing the the side that shouldnt release air. i could a very little bit.. i mean like a fraction of what i could blow threw the other side.
Old 08-25-07, 06:34 PM
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um hailers, where is this in the fsm? becuase i cant find 1A and up on your pics?
Old 08-25-07, 07:41 PM
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It's in the FUEL SECTION.

I doubt the coils are suspect at all since it does start.

I was thinking when you checked things out that the afm signal would be missing due to a plug not being connected up. And also look at 2B the boost sensor signal. Does it match the FSM readings at all? Should.

I know you can only check with the key to ON. By the way, all the grounds should be checked with the key OFF and the plug pulled off the ECU. Check the wire on the Plug not the ECU when checking gnds.
Attached Thumbnails ITS STARTS!..then dies : (-onetwo.jpg   ITS STARTS!..then dies : (-oneone.jpg  

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Old 08-25-07, 08:02 PM
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Question Update

okay, i got the pin outs. but before i post them i am wondering... hailers you diddnt post 1 U thre 1 A in your pics. do i not need them?

these are the pin outs for my s4 TURBO ecu corrent?

these are the pin outs with the car in ON, member the car wont idle ; D

terminal pinned volt spec
2A v rev 5 4.5 -5.5
2B pressure sensor 3.8 2.3-2.7
2E afm .1 .4
2g throttle sensor 2.47 1
2h atmospheric pressure sensor 3.77 i live in pittsburgh pa
2i water thermo sensor 3.27 .4-1.8 !??!?! says something
about the engine being warm?

3c injector rear pri 11.9 12
3e '' front pri 11.9 12
3h '' front sec. 11.94 12
3i main relay 11.9 12
3j bat 11.96 12
3f inj rear sec. 11.9 12

here are some of the other ones that dont come out to spec.

1u coil with ign. T 4.04 4.4
1w heat hazard 11.1 1.5
1x coil with ign. .57 0
2k twin scroll solenoid valve 11.7 2
2p reliefe solenoid valve 11.7 2
3g ground 0 .01

ALL of these, im going to double check to make sure that i took the readings right... soo whats wrong with my car!?
Old 08-25-07, 08:09 PM
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Yeah. Look at 2E. You show point one and point four.

With the key to ON, the reading should have been four volts dc approx. Your nowhere near that. The ECU isnl't seeing the afm signal so the engine isn't going to run after it starts.
Old 08-25-07, 08:19 PM
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The problem is there are NO connectors b/t the afm and the ECU other than the ones on them.

So make sure the ECU plugs are connected. Then go to the AFM.

Pull the plug off the afm. Put your meters neg lead on a known gnd. Then, with the key to ON, touch the wire that is colored brown/white. It should show 4.5 to 5volts dc. Write back.

While there, turn the KEY TO OFF. Then put the meter on ohms. Negative lead of the meter to a known gnd.

Touch either of the brown/black wires in the electrical plug. They should read something like 0.5 ohms or so
Old 08-25-07, 08:54 PM
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I guess it could be a bad AFM .....but TWO???????
Old 08-25-07, 09:35 PM
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oh wait, **** i had the afm off let me connect it. here...lol i just a laptop so im out at my car at this very instant. go TOSHIBA! guess what i got it for...thats right, tuning!....and school
Old 08-25-07, 10:53 PM
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Lightbulb update !

okay sorry about the first post of the numbers, the first catagory was the terminal, the second number was what i got. and the third was what the specification is.

okay, all of was i posted STAYS THE SAME except for the following..
after plugging the AFM back IN, these are the results

term, pinned spec
2e afm 2.74v .4v
2j afm intake air temp sensor 3.1v 2.3
2k twin scroll solenoid valve 1.62v 2.0
I DO NOT THINK THIS WAS ADDED BEFORE
3D fuel pump resistor relay 0v 12v

it says that it should drop back down to 2 volts, if that means anything

Last edited by skatingsamurai; 08-25-07 at 11:12 PM.
Old 08-25-07, 11:28 PM
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wtf is goin on here, i went to unflug the afm and all of the sudden i head this click. and i started to move it and it clicked again....okay...it started clicking more as i started to fiddle with it..then out of curiosity, i started to cut into the harness(not cutting ANY wires) and i notice that if i move it a certain way i hear that clicking noise!! wtf is it???? its accually quite loud and its comming from somewhere on the throttle body....last time i checked, moveing wires shouldnt turn something on or off right? **** it, im goin in.


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