Canuckican
Well-Known Member
- Joined
- Nov 4, 2017
- Threads
- 18
- Messages
- 187
- Reaction score
- 229
- Location
- NE Wisconsin
- Vehicle(s)
- 2016 Mustang GT Premium - Race Red
- Thread starter
- #1
This is Mustang number seven for me. My last one was a Screaming Yellow 2016 GT Premium I sold to help pay for the kids' college. That's all over so I went on the hunt for another Mustang. I looked at some 1998 Cobras, 2004 Mach 1s, yellow 2005 GTs, a couple of 2014 GTs but really had my heart set on another 2016-17 GT Premium.
I located a nice 2016 GT Premium automatic for sale in Southern Florida with low miles and a clean CarFax. I'm in the upper Midwest so a personal inspection was not practical. I had the dealership answer a bunch of specific questions. I particularly wanted one that was not beat to death and was as original as possible. The answers I got back stated it has stock exhaust and engine, the only identified mods were lowering springs, Koni shocks and Maximum Motorsport caster plates.
I decided to take a chance on it. Imagine my surprise when it arrived the next week and I found on it a 2018 intake manifold, BBK long tube headers, BBK hi-flow cats and a MBRP race catback. I expect that in order for this combo to run, there must be a custom tune of some type required but no tuner came with it.
After the car was down off the car hauler, I fired it up for a quick test drive. It started okay but idled terribly until it warmed up a bit. I also saw that it only averaged 12 mpg over the last 7K miles. That is much less than the 19.5 mpg I averaged on my virtually identical yellow 2016. Hmmm.
The car was only showing about 25 miles to empty so I stopped and filled it with 87 octane (unaware of a potential 91 tune issue). I barely made it the 8 miles back to my house, it was now running so poorly that I had collected P0300 cylinder misfire on cylinders 1,2,3,5,7,8 as well as P2196 O2 sensor 1 stuck rich and P2198 O2 sensor 2 stuck rich.
I popped the hood and saw it actually had a 2018 intake on it. The four connectors at the back of the intake are not plugged into anything (locked IMRC?) and I was told that this can cause a rough idle when cold. A custom tune is needed (I think) to lock the IMRCs. Hmmm. Then I dug further and saw the BBK long tube headers and then the BBK hi-flow cats. And the MBRP logo on the cans on the cat-back. So yeah, not quite a stock system.
I parked it in my garage and started analyzing further. I found and fixed a few vacuum leaks but they were trivial. What really surprised me is that the car would no longer start at all. It would crank and crank and if I opened the throttle to shut off injectors it would stumble/run for a few seconds but it sounded painful. And a very strong odor of gasoline too.
I let it sit the rest of the day and the next day I pulled the plugs. All 8 were wet with fuel and covered in soot. I gave them a good, gentle cleaning and re-installed them. The car did start but did the spastic stuttering and shut off. I was told to try starting it with the MAF disconnected but it did not help. I cleaned the MAF with MAF cleaner just in case but no change. The gas I got is at a highly-busy station so it's probably not bad gas. Oh yes, since it is now not starting on a full tank I threw another cheap part at it... vapor canister purge valve, but no change.
I am grasping at straws but I wonder if the previous owner removed the custom tune from the Mustang so he could keep the tuner and now the car has a factory tune with a bunch of changed bits not working properly. Would a Mustang totally cease to run if a stock tune was tried with the intake, long tube headers and hi-flow cats this car has, or would it still run decently well but just a bit sub-optimal? I don't really fancy forking out $900 for a tuner and custom tune to find out. There aren't that many places doing custom tunes for 2018 intakes on 2015-17 GTs it seems.
I am very tempted to just revert the intake to stock, replace the long tube headers and hi-flow cats with OEM and get a factory tune from Ford. Really I don't care if this car has 430 hp or475 hp. I just want it to reliable and fun to drive.
I've been trying to find someone locally (NE Wisconsin) to hire to try to sort it out but it's a challenge when I'd have to get it towed wherever I take it.
I miss my yellow 2016!
I located a nice 2016 GT Premium automatic for sale in Southern Florida with low miles and a clean CarFax. I'm in the upper Midwest so a personal inspection was not practical. I had the dealership answer a bunch of specific questions. I particularly wanted one that was not beat to death and was as original as possible. The answers I got back stated it has stock exhaust and engine, the only identified mods were lowering springs, Koni shocks and Maximum Motorsport caster plates.
I decided to take a chance on it. Imagine my surprise when it arrived the next week and I found on it a 2018 intake manifold, BBK long tube headers, BBK hi-flow cats and a MBRP race catback. I expect that in order for this combo to run, there must be a custom tune of some type required but no tuner came with it.
After the car was down off the car hauler, I fired it up for a quick test drive. It started okay but idled terribly until it warmed up a bit. I also saw that it only averaged 12 mpg over the last 7K miles. That is much less than the 19.5 mpg I averaged on my virtually identical yellow 2016. Hmmm.
The car was only showing about 25 miles to empty so I stopped and filled it with 87 octane (unaware of a potential 91 tune issue). I barely made it the 8 miles back to my house, it was now running so poorly that I had collected P0300 cylinder misfire on cylinders 1,2,3,5,7,8 as well as P2196 O2 sensor 1 stuck rich and P2198 O2 sensor 2 stuck rich.
I popped the hood and saw it actually had a 2018 intake on it. The four connectors at the back of the intake are not plugged into anything (locked IMRC?) and I was told that this can cause a rough idle when cold. A custom tune is needed (I think) to lock the IMRCs. Hmmm. Then I dug further and saw the BBK long tube headers and then the BBK hi-flow cats. And the MBRP logo on the cans on the cat-back. So yeah, not quite a stock system.
I parked it in my garage and started analyzing further. I found and fixed a few vacuum leaks but they were trivial. What really surprised me is that the car would no longer start at all. It would crank and crank and if I opened the throttle to shut off injectors it would stumble/run for a few seconds but it sounded painful. And a very strong odor of gasoline too.
I let it sit the rest of the day and the next day I pulled the plugs. All 8 were wet with fuel and covered in soot. I gave them a good, gentle cleaning and re-installed them. The car did start but did the spastic stuttering and shut off. I was told to try starting it with the MAF disconnected but it did not help. I cleaned the MAF with MAF cleaner just in case but no change. The gas I got is at a highly-busy station so it's probably not bad gas. Oh yes, since it is now not starting on a full tank I threw another cheap part at it... vapor canister purge valve, but no change.
I am grasping at straws but I wonder if the previous owner removed the custom tune from the Mustang so he could keep the tuner and now the car has a factory tune with a bunch of changed bits not working properly. Would a Mustang totally cease to run if a stock tune was tried with the intake, long tube headers and hi-flow cats this car has, or would it still run decently well but just a bit sub-optimal? I don't really fancy forking out $900 for a tuner and custom tune to find out. There aren't that many places doing custom tunes for 2018 intakes on 2015-17 GTs it seems.
I am very tempted to just revert the intake to stock, replace the long tube headers and hi-flow cats with OEM and get a factory tune from Ford. Really I don't care if this car has 430 hp or475 hp. I just want it to reliable and fun to drive.
I've been trying to find someone locally (NE Wisconsin) to hire to try to sort it out but it's a challenge when I'd have to get it towed wherever I take it.
I miss my yellow 2016!
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