Mustang Missing like CRAZY. unless I gun it

[TenorPlayinGuy]

bah... Well I sent out my injectors for cleaning and replaced all the pintle caps and o-rings, when i did my head gasket. But like I said this was all happening before my head gasket swap also. It doesnt feel mechanical at all. Cuz as I said when It wants to it pulls very nice. I also noticed some backfiring. So I am pretty sure with some sensors and other wiring along with a replacement of EVERY vacuum line on the motor I should be set.

 

[TenorPlayinGuy]

^^^

 

[TenorPlayinGuy]

im also gonna be installing a 255lph fuel pump that i have... I dont want this bieng a fuel issue later on. I know im running rich. But that will hopefull get fixed by this weekend

 

[TenorPlayinGuy]

ohhhhh Man... I swapped out the injector harness Found a HUGE vacuum leak, replaced the O2 sensor harness. And cleaned the HECK out of my throttle body while installing my new IAC. MY MOTOR RUNS LIKE NEW!!! ... now all i need is anew battery and Im good to go. ( mine suffers bad from heatsoak)

 

[cjhenry01]

Where was your vacuum leak?

 

[Curse]

Love it when it turns out to be an easy fix

 

[TenorPlayinGuy]

the leak was the Big vacuum line that goes to the Tree and also the one for the MAP sensor

 

[TenorPlayinGuy]

but then again its starting to do it again. hmmm

I just replaced my EGR, those solenoids on the passenger side fenderwell. which supply vacuum to the EGR stuff. My car idles fine, WOT fine. But trying to drive normal it jumps a bit. ( kinda notice it more with the stock 87 suspension too) Im gonna put her down though. As I have new parts to install. like my TFS Twisted Wedge heads (BEEN WAITING SINCE I STARTED WITH STANGNET TO GET THESE BAD BOYS) a Cobra or Performer RPM intake(which would be best) and my car to Mass Air. So Hopefully in the transition with a whole lot of new parts the problem will just go away. Im rebuilding the tired old five - oh too. So that should rule out a lot of things later on.

 

[z9_87]

I just fixed mine, it was a plug wire bad, I couldn't get it to arc so I just wrapped the driver's side wires with rubber elec heat resistant tape and problem gone. So it was a plug wire one of 5-8.

 

[TenorPlayinGuy]

yeh I always had a prob with number 6 but its not showing anything at the moment with my new FMS plug wires. im just gonna rebuild the motor anyway. And replace everything. If it dont fix it Imma be pissed. I really dont want this problem while trying to smoke an LS6. PUT PTUT VROOOM

 

[z9_87]

Same thing here, while it was missing at low rpm's i pull up next to a civiv, and they are laughing at me, so I ask if they want to race a 7cyl thunderbird. Little did they know the miss cleared up about 2k rpms Makes a good sleeper!

 

[TenorPlayinGuy]

yep it does... I did a vacuum test and it is pullin a real good 17-18in but when I even lightly tap the gas the vacuum goes NUTZ all the way down to like 2 or something. that cant be right?

 

[sweet88gt]

I read in you post above that you replaced the EGR soleniods at the strut tower, but did you check the EGR vavle? Its just a thought but if the EGR is opening too fast or is the problem you may only have part throttle problems because the EGR doesnt operate at WOT. Cap off the EGR vac line and run the car as normal and see if there is any change in the miss. Its worth a shot at this point right.

 

[Euphoric306]

not even in the same world, but my old 84 had a VERY bad missing problem, at idle, during normal driving, only time it seemed to clear up was when engine was warmING, it would return once at normal temperature.

everytime we replaced something, it would go away for a day, a week, or an hour, then come back.

we eventually gave up and sold it, funny thing is it went away when the guy was testdriving it, nice score on that

anyway, ive always suspected the brain was just fried, but never got around to actually fixing it

ive heard a few other horror stories about missing problems that go away and then come back a little later, sorry u got caught up in that too

hey i noticed ur in redlands... im 17 and over here in norco... summers been hell on the stang huh, damn heat.

i cant remember whether u said u ran the codes or not... but that might be a wise idea

they help a lot, especially with the OTC manuals i have

 

[TenorPlayinGuy]

ran the codes and got the usual EGR and other errors for O2 sensors. EGR is brand new with those solenoids. The heat is nothing. my stang runs at a stable 180* even if I push it. just gotta remember to keep the water up.

 

[Euphoric306]

hehe just found a brand new radiator at pickapart for 50 bucks, cleaner than hell

my old one was leaking about halfway down every three weeks, not very good.

i get better gas mileage now that i swapped out for a 195 tstat, maybe its just me?

my a/c stalls the motor, so i gotta run with the windows down
4-60 a/c all the way

well, only two windows, so 2-60

might try checking grounds, or creating your own grounds to see if it goes away

checked resistance in coil?

not sure if 87's have a act sensor (air charge temp) but that probably wouldnt fix much anyway

if u feel up to it, maybe swap the brain out for a junkyard 5.0 ecu, see if it does anything, cant be more than 40 bucks or so

sorry i cant offer much help, its pretty late and i know how frustrating intermittent problems can be, especially when they give u false hope in going away

update any changes

 

[Euphoric306]

did u ever rebuild the distributor... ive heard the pickup coils can go bad and cause some heavy missing

 

[TenorPlayinGuy]

yeah thats next on my list. I did replace the act . Most my sensors are brand new, except for my O2's. Those are next and are well kinda the most expensive. ill checkout with the distributor and give you all an update.