Mongoose in but runs PIG rich

AmBo

Active Member
Feb 3, 2004
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1
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New Jersey
Okay, the mongoose is in but she runs HORRIBLE. She's leaking fuel and puffing smoke. We don't know what the problem is. The MOngoose tune has been loaded and she runs HORRIBLE. It seems the tune doesn't account for the bigger injectors.

We loaded the stock tune to see how she ran on the stock tune and she ran JUST the same. Back to the MPH tune and same result. Seems the tune is bad? :shrug:

I'm going to try to limp her home but it's a long drive and I'm not thrilled to do it. I don't even think Tim is in the shop on Mondays. I think I'm going to have to wait till at LEAST Tuesday to even talk to anyone over there...I'm pissed and upset as hell. I shoulda just shelled the $500 and had a shop do the F'ing thing right. :(
 
Man, I would NOT drive it if its leaking fuel. It would be an absoloute shame to see something bad happen with that.

Good luck getting the bugs worked out, hopefully its something minor in both cases.
 
I would not even run or or dive it with the stock tune in it. you know 100% that tune is going to be off.. If the thing is running that bad with the supplied tune I would not drive it that way either.

when you say fuel leaking do you mean leaking fromt he fuel system or just un burned fuel runing out the tailpipes? If you have already double and triple checked the install and think it is the tune I would just wait for support from MPH.

I would not drive the car like that but that is me. I would try to figure out what is wrong before you drive the car around. then again I have a car trailer so I never have to worry about getting it from point a to point b is free for me.
 
hotmustang331 said:
Check for ANY vacuum leaks...I seriously doubt its his tune. And make sure your loading the tune in correctly.

That's what I told him.

AmBo - you should also make sure the IAT is hooked up properly and functioning; the car will automatically limp if the signal is out of range. Did you install it in the coupler between the blower and discharge tube?
 
BennyDaBall said:
That's what I told him.

AmBo - you should also make sure the IAT is hooked up properly and functioning; the car will automatically limp if the signal is out of range. Did you install it in the coupler between the blower and discharge tube?

It's installed in the discharge tube right after the first bend. It's not the IAT. It's the LMAF. When we plug it in, the car spits fuel. When we unplug it, she runs fine. Little of a high idle, but fine none-the-less. I was able to take her out and have some fun with her
 
Yea I hope that this is the problem. It really seems like it is.

I wouldn't know how boost is though as I couldn't really get on her at all. All I know is she felt like a complete new beast <3,500 and that's when the boost is just spooling up! I can't imagine what she's going to feel like once all is said and done :)
 
Dont get into boost at all with the MAF unplugged. Unplugging it puts it into limp mode, and there is no guarantee that you will be rich enough not to pop the engine under boost, and it does't guarantee that the MAF is the problem. Did the tuner know what size injectors and what maf you had when they tuned it?
 
What size injectors are you using Vs. what the tune is calibrated for? I had almost the exact same problem. If you are blowing fuel out the tail pipes be very very careful. You could create some serious cylinder wash. The fuel will pass down your cylinder walss washing away the oil. That's bad news. If you do it long enough it will wear your block and destroy your rings.
 
This is the mongoose kit from Tim over at MPH. His tunes are supposidly dead on 99% of the time so I REALLY don't want to blame his tune.

We only leaked fuel for maybe a combined minute of time at idle. Never had a load on it.

I can't get into boost as boost kicks in at ~3,500 and getting there using no more than 1/4 throttle is extremely difficult. lol. However, just totting around in limp mode she drives perfectly fine.

I'm putting the new L-MAF in today. I guess we'll see if this was the problem in a couple hours.
 
AmBo said:
I too am waiting to tell you how sweet the power feels. Although for some reason it feels like that time is never going to come. :(

Aww don't say that! I felt the same way after breaking the oil feed hose installing it, then waiting a week to recieve a new part...low and behold they send me the WRONG part! Another few days and I had it going "FINALLY". :rolleyes:

Did you ever find any vacuum leaks? You told me you were reading 11kg at idle correct? Most cars usually idle between 15~20 - and I know once when I forgot to hookup a vacuum hose It idled around 10 and ran rich as hell and could barely stay started.

Another thing you may have missed (just throwing it out there) is the mounting orientation of the bypass valve. It's a oneway setup - one in one out, not either way. That could effect idle and vacuum also.