injectors flooding on 88 tsi

[rcm]

Ok i have read the posts and have a 88 fsm.The injectors are dumping fuel.So i got another set

here on the forum.Same thing.I changed the oil because it was full of gas,fuel filter,plugs,

jump fuel pump connector and watched inside the throttle body and no leaking.So i checked

the clips which were already changed.Thought maybe had them backwards.Checked wire color to the

primary and secondary seem correct according to manual.They are not soldered just twist tied.

Unplug them and it will start for a few seconds.I checked voltage with key on and both have voltage

at the same time on the right side clip.The computer has been changed also.So where to go from here.

[rcm]

ok had the wife crank car while i looked into the throttle body.Both injectors are running at the same time flooding

it until it dies.So what causes that????

[NotStock88]

if you know the ECU has been changed you need to find out what ECU you really have. I remember when I was TBI on my 88 that I could un-plug the 2ndary injector and the car would still fire right up and idle fine - this was a quick check to be sure i had the injector clips plugged in correctly.

[rcm]

Well if i unplug secondary it will start then die.This is what it was doing to the guy i got it from

and he changed the ecu but no change.But the original injectors were leaking but these dont,it seems both are pulsing

all the time.

[vbrad511]

Hit Harbor Freight or Autozone and get noid light to check for injector signal.

 

http://cgi.ebay.com/ebaymotors/ampro-6-pc-noid-light-set-_W0QQcmdZViewItemQQhashZitem1c13d7b53bQQitemZ120591988027QQptZMotorsQ5fAutomotiveQ5fTools

 

It it's really pulsing the injectors full time it sounds like either the ECU has shot craps (which is rare)or you've got some wiring issues that you're gonna have to chase down. More normally the injectors themselves get some junk in them and the stick open. If you pull the OVCP off with the injectors unplugged and have the wife crank the car, you should be able to shine a light into the TB and see if anything's dripping or spraying. If your first injectors had junk in them it likely came from somewhere in the fuel system. If you haven't flushed things and/or changed filters there's still junk in it and it can muck up your replacement injectors too.

[rcm]

Ok i unlpugged the secondary..It will start and run rough as long i as i hold it at 2k rpms.

If you let up it stumbles and dies.

[rcm]

Well crank it and shine light in no fuel.Run jumper for fuel pump no fuel.Try to start with clips in and both spray

at the same time while in idle mode.Are both clips need voltage with key on?

[Indiana]

What year is the car and what is the ECU part # on the front of the case?

 

You bought used injectors instead of having yours cleaned?

 

Cleaning would have likely been less money and took the same amount of time.

[rcm]

well my primary plastic was broke along with the clip so i tried some used ones

from a guy here on the forum.The car was doing the same thing and the guy put in a rebuilt computer.

The number is md120197 and the build date is oct 1987.

[starquestG54B]

your maf could also be on the fritz aswell.

[Caliber308]

well my primary plastic was broke along with the clip so i tried some used ones

from a guy here on the forum.The car was doing the same thing and the guy put in a rebuilt computer.

The number is md120197 and the build date is oct 1987.

 

The ECU (MD120197) is correct for 1988/89 model years.Check that your Injector clips are wired properly. Yellow/White and Yellow/Black to the Primary. Yellow/Green and Yellow/Blue to the Secondary. Solder ALL the wire connections.The Black injector is the Primary, the Blue injector is the Secondary.You might want to check your Fuel Pressure Regulator and Fuel Pump pressure.Go here to download the Factory Service Manual: http://starquestgarage.com

 

 

Bill

Edited December 28, 2010 by Caliber308

[rcm]

Maf was changed too.Yw and yb to primary,Yb and yg to secondary is what i have.But does the voltage signal

go to the right clip on both injectors?Being not soldered will make it flood?

Oh i did put a vaccum pump on the fuel pressure regulator and it wont hold

any pressure just drops to zero??Maybe bad?

Edited December 28, 2010 by rcm

[Edde]

Maf was changed too.Yw and yb to primary,Yb and yg to secondary is what i have.But does the voltage signal

go to the right clip on both injectors?Being not soldered will make it flood?

Oh i did put a vaccum pump on the fuel pressure regulator and it wont hold

any pressure just drops to zero??Maybe bad?

 

The regulator operates on boost not vac. If after running the car or at any point you pull the lower vac line from it and get fuel - it's toast.

 

The injectors should have voltage on one wire at all times. They get grounded to make pulse. Like many other items on the car. You should not get fuel spraying from both inj at startup though.

[Caliber308]

The regulator operates on boost not vac. If after running the car or at any point you pull the lower vac line from it and get fuel - it's toast.

 

The injectors should have voltage on one wire at all times. They get grounded to make pulse. Like many other items on the car. You should not get fuel spraying from both inj at startup though.

 

Here are my experiences with dumping fuel: Stuck wide open (Bad) Secondary injector and malfunctioning Fuel Pressure Regulator.Like Edde said. If you have fuel in your vacuum line to the FPR...It's TOAST. Also, make sure your Fuel return hose is clear. Remove it and blow into it. You should hear the air entering the gas tank.

 

Bill

Edited December 28, 2010 by Caliber308

[rcm]

No fuel in the vaccum hose.Will try return line,And i am going to replace the clips and solder them,heat shrink

to insure thats correct and wire it by the fsm diagram.I have done them before with no problem but this

guy just tied them and taped it and thats been a few years ago.

[natallica]

I'm pretty much a "noob" when it comes to offering any advice, so if this is wrong someone experienced slap my wrist! But I just had this same problem and I went through the same things as you...double and triple checked everything. Soldered new clips, checked the injectors... yada, yada, yada. Turns out the throttle cable was adjusted way too tight and during startup it was dumping in the fuel and flooding a fresh rebuild (this was the first few startup attempts ) too the point it was puddling up on top of the throttle plate approx 1/4" or more. After changing the oil 3 additional times then going through the TPS/ISC reset procedure it ran fabulous (noticed "immediate" improvement at step # 2-remove slack from throttle cable ), also not having the OVC pipe on kept causing it to die after about 30 seconds till some air was forced in, it wouldn't idle well at all before that.

 

Then again, my lady was a basket case when I got it (throttle body was in pieces in 2 boxes and I had to pick from 3 sets injectors before finding the 2 that worked), so there's no telling how it got screwed up. I hope you get it figured out soon. I know how annoying it is to keep replacing oil and filters but not being able to leave the garage...and knowing what I was doing to my new motor was making me want to throw up. But it's all better now.

 

Good Luck

-N8

[rcm]

I will look at that today and see what happens,checking return line on regulator,new clips,then maybe set tps if

that doesnt repair the problem.

[DzNutz]

Definantly check the throttle cable and be sure it is slack, also be sure the MPS is reading .9v at idle and that the TPS is working as it should. Had a kid here was running pig rich because his TPS was messed up telling the ECU that he was at WOT all the time.

 

Idle set procedure

[rcm]

I think cable is too tight now that i think about it.Not sure if they messed around with the tps

but probably did.

[rcm]

would the cts be bad going in full choke mode maybe?I had the radiator out to be rotted and just got it back

in today.

[DzNutz]

CTS woould make it idle weird but shouldnt fire off both injectors...... thats why I am leaning toward the tps telling the ECU you are at wide open throttle since both injectors are firing.

[rcm]

would i need to check the voltage to insure it is 0.48-0.52 first?Then try to adjust or get another one.I cant do

the idle procedure since it wont run.The throttle cable did have about 1mm slack in it.I do know when the key is

on the throttle plate opens a 1/8 or so.

[Edde]

I doubt the tps setting would have that much effect unless it's seriously bad. But the test would be a sweep test. Using an analog volt meter on ohms - find the correct prongs and slowly move the throttle plate (or tps if removed) from closed to wide open and watch for spikes or dead spots in resistance. If it doesn't move smoothly or spikes at some point it's messed up. In theory I guess it could do what is being proposed - a full spike in output at or near idle.

[vbrad511]

Still baffled on your injector issue, but something you posted...your pressure regulator won't hold vacuum? If not, it's bad. Doesn't matter if it operates primarily on boost, it should hold vacuum.

[rcm]

Yes i put my hand pump on it and try to pull up 15psi and it drops quick to zero.I was thinking tps is bad,regulator,

Or the regulator return line.