Mustang5090

Hey guys, Just finishing up my mustang re build, everything is gravy except im still have the same problem i had when i took the car apart, When its dead cold like from sitting overnight and i fire it up it always starts but after it kicks down to idle it stalls, The only way for this not to happen is if when i start it i hold it at the high idle for like 30 seconds to a minute, My setup is rather mild just 24 lb injectors f 303 cam, long tube headers 1 piece, bbk cold air intake ud pulleys stuff like that, I always thought it was the 02 sensors cause they where bad in my old setup thought that was messing with the fuel curves at cold start but i guess not, its got brand new sensors on it now as well as a lot of other brand new stuff haha, Oh also the Smog pump is deleted and the vacumm lines plugged, Any help would be great

enix187

When you say you deleted the smog does that mean you fully remove it or just plugged the vaccum lines? If you didn't remove it I would say your egr is stuck open causing a lean condition when its in open loop. Pull codes and report back

Mustang5090

I totally removed the smog pump from the car and plugged the vacumm lines, it didnt do this untill way after i removed the smog pump though, or maybe thats just because i took the smog off in the summer and now its winter, but im not too sure, im at work right now im gunna try and pull some codes tonight, any other ideas till i can do that?

enix187

doesn't sound like you removed the egr at all, the egr valve can stick open and cause it to run lean when you start it, if you didn't plug the lines on the back of the heads then you didn't really remove the egr, do you still have the solenoid on the car?

Mustang5090

I cut the tubes that go to the back of the heads crimped and welded them shut, the egr valve and solenoid themselves are still on the car, should i mock up a block of plate and remove the egr valve and accuator too? and obviously plug the vacum lines that go to that as well.

enix187

wouldn't hurt, I'm sure once work lets out (I'm in college hours are weird) some one else will chime in to offer other suggestions

Mustang5090

Come on guys i could use a little help here, Just a little about my build, I had a 1990 Lx 5.0 that the frame rails rotted out of right above the K member, I loved the car so much that i wanted to save it and make new rails and put a 5 speed in cause i blew up the racing aod i built 8 times haha, but when i went to do the five speed i just realized it was way to far gone to save and i should cut my loses, So i picked up a 91 lx 4 cylinder roller for 250 bucks, parked em side by side and started stripping them out, have a lot of extra stuff if anyone needs anything, but anyway the roller came with no motor just a interior and some wheels and a gas tank, so i stripped that down to the complete chassis with the rear diff still in and did the same to my 90, than i happened to get a job at the local napa and with the discount i got i decided it was time to do big things, re did all the suspension on the new roller chassis all new shocks control arm bushings rack and pinion tie rods ball joints wheel bearings, i took the 8.8 rear out of my 90 and rebuilt it with 3.73's and the carbon fiber limited slip re build kit from the 03 04 cobras , all new brakes drums etc, new shocks control arm bushings also went with eibach pro kit drop springs all the way around to bring the stance down a bit make it a little meaner, the motor is mostly stock f 303 cam 24 lbs injectors, plenum spacer, 75 mm throttle body calibrated mass air, under drive pulleys, long tube ceramic headers, when i had the motor out of the car i cleaned up the block a a bit to get the raw oil residue off of it and went through and did all new valve cover gaskets, valve covers, oil pan, oil pan gaskets rear main seal all with fel pro perma dry gaskets which i highly recommend, all new power steering hoses coolant hoses, made my own spark plug wires from an accel kit also got the accel cap and rotor, msd blaster coil, brand new flywheel, Stage III zoom clutch from napa equivelant to a centerforce clutch, and for the trans i went with a re built world class t5 with a pro 5.0 short throw shifter, I swapped all the harnesses and dash and everything from the 90 into the 91 also the whole interior everything, Also new gas tank, and lots of odds and ends, pretty satisfied that i basically went through my whole entire car, I have a lot of pictures of the process that i should be able to post on here soon just working too much but im not complaining because my job helped me get this done as i had recently got layed off just as i had both cars down to the bare bones, so my project had stalled for 2 months up untill i got the job at napa and 2 months into that i went on a holiday and started ordering everything i needed and in the passed month ive worked on her every weekend night and day and now she in rolling chassis drove her for the first time last weekend around the block and i couldnt be any happier sorry if this isnt related but i love this car i have a very large passion for it and i know you guys do too and i know when ur having problems with your car and your just about to give up its nice to hear a story like this to remind you that you love your car and someday it will be perfect just the way you want it cause i just remember all the times doing this project that i just wanted to say ohh the hell with this! but something kept me going and the feeling i have now as im typing this is the result of a lot of hard work and i cant begin to express the amount of joy i feel hahahaha

dreamer1uk

Is your MAF calibrated for those injectors? Tune? What about the idle relearn?

zebo87

how does it react when driving cold. does it stutter or anything like that. how about when you get on it wot. what was the result of pulling the codes. try cleaning your maf.

Mustang5090

My MAF is calibrated to those injectors as far as i know, i brought the car like that with these injectors and maf and it always ran fine. And the isssue im having is only when its cold, got my scanner back from my friend last night going to pull codes tonight, always runs fine at wot, and always starts up fine once its warm, im just having this issue on cold starts after leaving the car sit for more than idk 6 hours, going to clean my maf today anyway havent done it in awhile,