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Boom's Boosted Bullitt

Great looking car and the power adder should multiply the fun factor. The 3 valve 4.6 is a great, dependable motor. No the easiest thing to work on in the Mustang however as just pulling the valve covers is a day long chore. I had a 2003 Mach 1 with the 4 valve. Was a blast to drive but that TR3650 was the clunkiest shifting transmission I have ever had. Hopefully it was just mine, but sometimes it almost took two hands to get it into first or reverse.
 
Thanks! I always liked this bodystyle. Wanted a Mach or an 01 Cobra vert (03-04 cobras are dead to me until the prices come back to our solar system)

This have the 2 valve. Might look at a coyote swap in the future if i can't get this engine to run properly.

The transmission in this car is super nice and tight. Reverse can be a bear to get into sometimes, even with shifting to fourth first.

Been having an issue where it runs lean on acceleration. Like really lean, 18:1+!

New pump, fuel pump driver module, pressure at rails 30 idle/35 when throttle is blipped. How is it going that lean when its getting more fuel pressure at the same time?

Found it had two codes, one relating to the FPDM. I cleared them both and checked for vacuum leaks, didn't find any. I also cleaned the MAF with a special spray.

Hopefully clearing the codes and cleaning the MAF help it run better.
 
SWEET!! I had a similar vintage SN95 back in the day. Sonic Blue Roush that I put a Kenne Bell twin screw on. Ran like a beast. Broke the trans twice but I will say it powershifted better than anything else I ever had!
Fuel pressure only keeps the injectors fed it has nothing to do with the program signaling the injectors to feed the correct fuel to the engine as needed. Seem to me you need to get the car to a tuner that can run it on a dyno and see what's wrong. Could be someone just bolted on the Vortec and failed to get it tuned correctly. Do it before you melt a piston!
 
I've been talking with a couple tuners online, they said its not likely a tune issue since "tunes don't change, parts and engine conditions do". The car did run well and did not seem to have this issue up till a few weeks ago, so i can understand what they're saying.

I haven't found any tuners in my area that work on anything besides Hondas, either. So I'm either paying minimum 80/hr for troubleshooting at a shop or 500-800 to put it on a dyno and hope that the shop knows how to tune it properly. :(

I did take it out for another drive, seemed to run a bit better with the one code cleared off and the MAF cleaned.

I'm honestly not wanting to sink a ton of money into this engine/set-up. I was originally thinking of pulling the Vortech off and starting fresh slate with a KB kit, but I can do a coyote swap for less then it'd cost to get a KB set-up. And make more power, reliably, with better MPG.

So my long term (hopefully) plan for this car is a coyote swap. I had planned to do supporting mods to the suspension and k-member to better prepare the car for the eventual swap. Good thing is the 4.6 and the 5.0 share the share mounts. Doing this would allow me to gather supporting parts for the swap here and there when I stumble upon a good deal or sale.

Heck, I'd almost be tempted to pull the Vortech off if I felt it'd run ok without it.
 
Is it possible the wideband 02 feeding the AFR is dirty/old, causing false readings to the ecu? This car has two or maybe even four O2 sensors. Has long tubes and an offroad H-pipe, too.

This car seems to have been built awhile back. Heck, the old fuel pump i replaced had a date code of 2010 of it. Plus I know its twenty odd years old so sensors and things are "end of service life" too.
 
Tunes may not change but that doesn't mean one was right from the beginning either.

O2 sensors can and do go bad and can give faulty reads. Not the cheapest of fixes to replace them but not horribly expensive either. I would also suspect possible injector issues. If they are really old they too can get dirty and not flow per spec. They can be cleaned and reinstalled but it really needs to be done using a real injector cleaning unit to do it right and get the best results. If you do pull them out be sure to vacuum around them well first. Same as you would when pulling plugs. Don't need any garbage falling into the ports.

Can you connect to the car and run a data logger while making a few runs to monitor AFR and other vitals?

Are there any real performance issues you can "feel" when driving it now? Does it bog or are there hesitations at discernible points of operation, for example? Is throttle response crisp? Or is the AFR reading your only issue/concern?
 
I noticed the scr tuner has a menu option for data logging, hopefully it'll work. I was thinking about that too, I'll give it a try here later.

The car does seem to hesitate occasionally. But if I back off or hammer the throttle it fixes itself and car runs great again.

The gauge almost always shows lean when throttle is given, no matter engine speed or amount of throttle given. This is why I was suspecting a fuel supply issue.

Some folk are also pointing fingers at the KB boost a pump. Device that amplifies the voltage going to the Fuel driver module and I'd imagine to the pump itself, potentially up to 17 volts. Thought about trying to pull the fuse on that and see if the car will run without it. I do have an upgraded pump so shouldn't need the boost a pump.
 
looked at the boost a pump wiring, can't unplug it as it appears the pump wiring goes though it. I turned the "boost" knob on the BAP all the way up and drive around. Definitely seemed to not run as lean for the most part, but it would still peg the AFR gauge lean on throttle. While I was driving the check engine light flashed on and then off so I headed back to the house. Check for codes, just the one P1000 code that will hopefully go away eventually.

I told the tuner to data log, and it was. But when I got parked and told it to stop, it froze. Turned the car off and pulled the plug. It turns right back on, but idk if it stored the data or how to read it.

Is there any chance it could be the Fuel rail pressure sensor? That the only part I haven't changed. I'm not even sure what the pressure is supposed to be, every where I look I get conflicting answers. Just hoping for an easy fix.
 
Been reading some things that bad plugs/coils can actually cause a lean condition, i would've guessed the opposite.

Can't see the plugs, but the coils are stock looking motorcraft, at 89k miles they are probably overdue for a replacement anyway. Figure plugs are cheap enough and it'd be good to pull the old ones to see what they look like, too.

I know I'm rambling on here and potentially grasping at straws, but I figure these items are due to be changed anyway. Hopefully they'll fix my lean condition too. Looking at some Accel coils and blower reccomended NGK TR6 plugs.
 
Having a hard time wrapping my head around a lean condition caused by coils/plugs. Fuel rail pressure needs are determined by volume/flow, really. Size of the rails and holes the fuel flow through all determine how much pressure is needed to get the right amount of fuel through and into the port in the allotted time. I always come across 35-38lbs being the go to number on these size engines.

I ran a KB boost-a-pump on mine as well. It got the stock fuel system up to the level of feeding the increased fuel needs of the boost introduced. Mind you, that was for about 8 lbs of fun. How much is your Vortech spinning up? You are running premium 93 as well, correct?
 
Yes, premium which is usually always 93. I'm not under much boost usually. When I hammer on it and it doesn't lean out it'll get to 5-8 easy. I started to run out of room at that point with speed limits and having to shift.

I don't understand the coils/plugs causing a lean condition either.

I am going to get the pressure sensor after the plugs and coils are installed if thebissues still present. Its the only thing left that touches the fuel system except for the injectors.

My understanding is that the pressure sensor in the rail sees the pressure drop and tells the FPDM to activate which tells the pump to pump at a given pulse.

So if the sensor is bad or reading low then the afr goes lean, causing the hesitation until the pump is told to send fuel time now which corrects the afr until the next time the throttle is opened to consume fuel.

I got ahold of a shop on the phone and explained my situation. They said on a car with so many unknown/old parts that getting fresh parts helps create a good baseline. They also stressed trying not to push through a lean condition, but to back off and let the afr correct itself until I get the issue resolved.
 
I'll probably put the car up on stand this weekend to check out the O2 sensors themselves. Want to see what model or brand they are to get new ones potentially.

My afr gauge was alot more bouncy on the drive back I noticed too. Forgot to mention earlier.
 
Had some points on the website so I went ahead and got the fuel rail pressure gauge just so I could say everything's new up to the injectors.

PSX_20230909_110112.jpg

Seems better, upon slow throttle up to 2k it barely budged from 14.5-15. A quick blip pegged the afr gauge but it came right back up to 12-13 and then quickly went back to 14.5 ish.

Need to take it out and see how it does driving.

Won't have my coils and plugs till Monday.
 
Horseplay said:
Having a hard time wrapping my head around a lean condition caused by coils/plugs. I always come across 35-38lbs being the go to number on these size engines.
Click to expand...

It made me scratch my head on why bad coils/plugs could cause a lean condition too, but I've been reading about O2 sensors and it seems to make sense now.

O2 sensors will tell the ecu to reduce the pulse of fuel injectors if they detect unburnt fuel in the exhaust. The issue seems to be more prevalent in low rpms when im putting around the neighborhood, so potentially in the higher rpms a bad coil/plug is firing more often so it would have a better chance of igniting.

Well see once the new coils and plugs come in. I did swing by the shop and took a look at the O2 sensors...all five of them.

PSX_20230909_173358.jpg

I didn't have my O2 socket amd didn't want to chance rounding them off, but I did notice sadly that they appear to be stock...like the coils packs

PSX_20230909_173423.jpg

Four of them clearly have stamped stamped on them. The fifth one didn't appear to have any markings. I'm pretty sure that's the wideband for the gauge.

So I'm really thinking about ordering new O2 sensors too. Does that seem like a good idea? I know it seems like I'm throwing parts at it, but I keep finding all these old probably original parts...

Once I get all new sensors and parts and if it still doesn't run them I will have it taken to a shop for a look at the tune. I just know they'll look at me sideways if I take a 22 year old supercharged car in with OEM sensors and ask them to tune it.
 
Thanks for that shops link. I sent them an email, hopefully they can provide a remote tune.

Had to travel down to Atlanta this last week for a work conference, so didn't have much time to mess with the car.

I did swap the plugs and coils packs before I left. The one coil and plug did look a bitbworse off then the rest. The rear pass side coil was different from the rest, also.

PSX_20230923_094734.jpg


Here they are all installed

PSX_20230923_094707.jpg
 
Reached out to Schraders tuning. They won't do a remote tune on a 4.6 that has forced induction. Too many potential issues.

I can understand that, seemed like a long shot.

I really am at the point where I might need to decide if I just want to remove the vortech or find another option. I can't see getting a different supercharger kit, seems like I'd be right back where I'm at now as far as tuning. Engine is an option, either 4v or coyote are 2 most likely.
 
Where are you now? You can't find anyone nearby that can put it on a dyno and tune it? Anymore there are such shops all over most metropolitan areas.
 
I did get a shop that called me back. Talked with the owner for awhile. The only thing I haven't done that the shop suggested is run an injector cleaner of any sorts, I don't think it'll do anything, but I'll look into it.

I'm gonna look at my schedule and see how far this shop is and see about trailering the car there. They have a dynojet in house and are an sct dealer/tuner. Told them I'm really only looking to have it run reliably and safe, not looking for more power then the block can handle. I have to assume it's got stock internals since I don't have any way to verify otherwise.

So we'll see. Hopefully should know more once I can get the car done there.

Living in the mountings makes it that much more fun finding these specific shops.
 
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