No start/bad id due to rich condition? Change inj., or buy IAB plate?

[TheUser]

No start/bad idle due to rich condition? Change inj., or buy IAB plate?

I hate to post this, but I could use some input. I can start my car up and it usually won't start the first time and I usually have to mash the gas (I know that closes injectors-which indicates a rich condition.) I have 30# injectors, which are too big for my combo, so I dropped the pressure to around 35ish to see if that would help, but then it started kinda bucking sometimes if I wasn't on the gas very much. The other day, I was turning onto a road by my work, hit the clutch, idle dropped, car died and wouldn't start back up, I think partially because too much fuel is making it flood its self out.

When I start it, it'll usually bounce around for a sec or two and then idle around 700 rpm and idle fine. I shut it off tonight after driving it up the road, and I tried to start it right back up and it wouldn't start. Went back out later and it fired right up. I'm reluctant to change injectors because of the expense of injectors and a different MAF-maybe I could find someone looking to upgrade as I need to downgrade, but that's always risky too.

I think there might be two problems here...idle problem and rich condition?

Basically:

Would it be alright to just drop fuel pressure from 38 and drive it w/ the 30's. Does it sound like maybe this could be fixed with one of those throttle adjustment things that goes in between the IAB and Throttle Body?

 

[HISSIN50]

as you know, the puter will adapt to the fuel pressure changes you make. i see the balance you are trying to walk - duty cycle versus injector squirt. im just not sure if what you are trying can work.

are you really sure it is fuel related? checked it with a FP gauge? checked for spark when it would not fire? dont forget ignition stuff (esp when it gets hot - cools off and works). ditto for FP though, as well.

i like your thinking about a couple separate issues (domino thing perhaps goin on). clean the IAC? remember the VSS should keep your idle up while rolling at idle and out of gear.

how about codes?

i know you know all this stuff ive said - im just tossing out what came to mind.
good luck bud.

 

[90mustangGT]

Do you have your MAF calibrated to the 30lbs injectors?

Did you check for vaccume leaks?

 

[TheUser]

Thanks guys:

-Check Engine light isn't on, so that means no codes right
-Cleaned IAC
-Fuel Pressure Guage on rail, although i've never really checked it when the prob. occurs; ditto for spark. Good thinkin'
-I would assume the MAF is for the 30's, but it came w/ the car like that
-I'm going to check vac w/ a guage today.
-I'm not sure it's fuel related 100%, but if I have to mash the gas for it to start, that kinda leads me to believe maybe it is running rich.

I'll play w/ it today and post if I have any other questions and/or results

 

[HISSIN50]

Thanks guys:

-Check Engine light isn't on, so that means no codes right
-Cleaned IAC
-Fuel Pressure Guage on rail, although i've never really checked it when the prob. occurs; ditto for spark. Good thinkin'
-I would assume the MAF is for the 30's, but it came w/ the car like that
-I'm going to check vac w/ a guage today.
-I'm not sure it's fuel related 100%, but if I have to mash the gas for it to start, that kinda leads me to believe maybe it is running rich.

I'll play w/ it today and post if I have any other questions and/or results

codes can be stored without meeting the criteria to trigger the CEL. always fun to see what (if any) codes have been tossed and stored in the KAM (even if the light did not illuminate).

im thinking you might get a code to lead you in the right direction of why you have to cut the injector pulse to start the car. that is a little funky.

that is all i can think of. good luck.

 

[TheUser]

just did a vac test on the front vac port of my cobra upper intake...12 at idle and 18 when revved to 2000 rpm...bad huh? I guess that means there's a vacuum leak right? Sounds like fun.

I did the warm up, turn off, try to start thing and it'll start if I don't push the gas most of the time, but it'll run up to about 1500 rpm one time and then die. If I push the gas to WOT and crank, it starts and then surges from 500-1500 and I have to give it revs to keep it from dying out, but if I give it a few revs to keep it alive for about 10 sec, it'll calm down and idle at about 700-800.

I'll try to get codes, but I suck at that.

I might swap my IAC from my LX to the GT and see if that does anything.

Maybe i'll double check the TPS, but i'm almost positive it's at .99v.

Sometimes when I drive it and come back, the dipstick is pushed up about 1/4 an inch, so I shove it back in...think that's related?

Also, forgot to mention I have an FMU on there from the previous s/c, but it SHOULDN'T matter. I've tried to get it off, but can't get those stupid "quick release" things off...i'm gonna try again today.

Thanks for all the help. Any other ideas would be awesome.

 

[jrichker]

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/article...c-iv_codes.html

IF your car is an 88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Walmart .

 

[TheUser]

Thanks Jrichker.

I did pull the codes 3 or 4 times just to see consistancy:

KOEO

85-Canister purge circuit?
85

This is confusing-it's output twice, which I thought it was only supposed to be output once

Seperator Pulse

96-Fuel pump circuit
96

What exactly does this mean? The fuel pump circuit is bad? The car runs, but I did have a period of about 4 days where it wouldn't turn on...that was about 2 weeks ago. I guess it's a hard fault from then since it hasn't been cleared...

KOER
94-Secondary air system inoperative
44-Air Management system inoperative
94
44

Is this the MAF and MAP?

Something else kinda weird is that these are 2 digit codes and the book lists 3 digit codes for 1991 and later

Can someone address these problems?

 

[ratrapp]

my car acted just as yours did.it wouldn't start unless i held my foot to the floor and then idled like crap until it warmed up.i tried a lot of sensors,coolant temp,air temp,iac,tps,new maf.finally i tracked it down to 2 injectors going bad causing my car to flood when started.i replaced them with 24s because i didn't want to buy 2 new stock injectors.even though i still have a stock19lb maf it starts great just performance is down until i can upgrade to a 75mm pro-m maf.

 

[TheUser]

you mixed 24's w/ stockers? lol, not so sure if I'd do that, but whatever floats your boat.

I would assume my problem is with one of the codes I dumped, I just don't know what they mean in laymans terms.

I took the MAF off, the whole thing, not the top box thing because I don't have the torx sockets w/ the holes, but anyway, sprayed some throttle body cleaner in there and let it dry, pulled neg. cable and all that. I thought it was doing better, but it's back to the same stuff.

Since my vac. was 12 at idle, there very well could be a vacuum leak of some sort, which i'm not too excited about tracking that down. I can only work on this thing on the weekends and winter will be here in a few months, so it may not run right until next year if then..oh well.

 

[ratrapp]

no,i put all 8 injectors in it,not just 2.

 

[TheUser]

Thanks Jrichker.

I did pull the codes 3 or 4 times just to see consistancy:

KOEO

85-Canister purge circuit?
85

This is confusing-it's output twice, which I thought it was only supposed to be output once

Seperator Pulse

96-Fuel pump circuit
96

What exactly does this mean? The fuel pump circuit is bad? The car runs, but I did have a period of about 4 days where it wouldn't turn on...that was about 2 weeks ago. I guess it's a hard fault from then since it hasn't been cleared...

KOER
94-Secondary air system inoperative
44-Air Management system inoperative
94
44

Is this the MAF and MAP?

Something else kinda weird is that these are 2 digit codes and the book lists 3 digit codes for 1991 and later

Can someone address these problems?

I got the probst book out and read a little bit. 85 is because I have my charcoal canister removed. 96 is because I unplugged the fuel pump one time when i had my keys locked in my car when it was running 94 and 44 I think are because I have GT40P heads w/o the thermosister things for the cats, but since I don't have cats, it's cool. Guess i'm gonna chase a vacuum leak