Jason's TBI thread

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sgtpoliteness
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Re: Jason's TBI thread

Post by sgtpoliteness »

Bill usn-1 wrote:Try scaling(mult) the AE/TPS AE table by 1.5.
Do not increase the AE/MAP table.

I think that was one of the first things I did a while back. I'll check it against the stock file.

EDIT: Yeah, nope. Once I went back to the stock tune to test I never redid the AE TPS table. I just did the whole thing by 1.5 and I'll try it out later, at lunch.


Babywag - Yeah, no kidding. We had one at my last job, which was great. I'll need to pick one up here eventually and that way Ethan, Blake and I can all use it. :D
1977 Cherokee Chief WT w/ 2" lift
360 (originally a 401)/TH400/QT w/ MM part-time
16197427 $OD junkyard TBI set-up
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sgtpoliteness
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Re: Jason's TBI thread

Post by sgtpoliteness »

That certainly helped. Throttle response is improved.

A couple weekends ago when I replaced my sagging, torn transmission mount I developed an annoying exhaust vibration. :roll: If it's not one thing it's another, right?
1977 Cherokee Chief WT w/ 2" lift
360 (originally a 401)/TH400/QT w/ MM part-time
16197427 $OD junkyard TBI set-up

FSJ Guy
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Re: Jason's TBI thread

Post by FSJ Guy »

sgtpoliteness wrote:That certainly helped. Throttle response is improved.

A couple weekends ago when I replaced my sagging, torn transmission mount I developed an annoying exhaust vibration. :roll: If it's not one thing it's another, right?
Head over to Hanksville Hotrods. He does SWEET exhaust systems!!! (And roll cages, too!)

http://www.hanksvillehotrods.com
Ethan Brady

http://www.bigscaryjeep.com

Jeepless, but I still have a lots of old parts in my garage!
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sgtpoliteness
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Re: Jason's TBI thread

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Those guys are great. They did roll cages for some of the race cars when I was at 3zero3. I was gonna go talk to them or BDM to redo the exhaust from the manifolds back at some point.
1977 Cherokee Chief WT w/ 2" lift
360 (originally a 401)/TH400/QT w/ MM part-time
16197427 $OD junkyard TBI set-up
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sgtpoliteness
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Re: Jason's TBI thread

Post by sgtpoliteness »

So I'm standing here, making pancakes and playing with my son in his high chair on a Sunday morning and my mind wanders briefly to my TBI setup. :oops: I've got AIR injection and it works and is all hooked up. I can't believe I never even considered this...wouldn't that effect the O2 sensor readings?? With the addition oxygen wouldn't the O2 think the mixture was much leaner than it really is?
1977 Cherokee Chief WT w/ 2" lift
360 (originally a 401)/TH400/QT w/ MM part-time
16197427 $OD junkyard TBI set-up

FSJ Guy
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Re: Jason's TBI thread

Post by FSJ Guy »

Yes it would. If it is actually working. ;- )

I re-plumbed my old system to constantly send the air to the catalytic converter instead of injecting air into the manifolds. This way, it passes a visual inspection.
Ethan Brady

http://www.bigscaryjeep.com

Jeepless, but I still have a lots of old parts in my garage!
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sgtpoliteness
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Re: Jason's TBI thread

Post by sgtpoliteness »

As far as I know mine still works. The D.V. seems to actuate and the pump is certainly working. What the devil should I do now? The Cherokee never came with a cat, so I don't need to do that. I'm not even sure if the '77's get a visual at the independent testing sites.
1977 Cherokee Chief WT w/ 2" lift
360 (originally a 401)/TH400/QT w/ MM part-time
16197427 $OD junkyard TBI set-up
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babywag
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Re: Jason's TBI thread

Post by babywag »

If it doesn't have to be functional, pretty easy to modify it, and it should fly if needed for visual.
-Tony
'88 GW (aka Babywag)
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sgtpoliteness
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Re: Jason's TBI thread

Post by sgtpoliteness »

Yeah, I'm pickin' up what you're puttin' down. I looked over my TSM and I think I can make an easy modification or two. I can't believe I hadn't thought about this earlier. Right now the PCM must be dumping more fuel than it really needs because of the additional air from the pump.
1977 Cherokee Chief WT w/ 2" lift
360 (originally a 401)/TH400/QT w/ MM part-time
16197427 $OD junkyard TBI set-up

FSJ Guy
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Re: Jason's TBI thread

Post by FSJ Guy »

If you haven't really noticed any difference, it must not be running too rich. <shrug>

It will be interesting to see if mileage changes.
Ethan Brady

http://www.bigscaryjeep.com

Jeepless, but I still have a lots of old parts in my garage!
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sgtpoliteness
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Re: Jason's TBI thread

Post by sgtpoliteness »

I've always thought is smelled a little rich, but that's not real accurate barometer. I'm gonna modify the DV and see how big of a difference it makes to my fuel trims.
1977 Cherokee Chief WT w/ 2" lift
360 (originally a 401)/TH400/QT w/ MM part-time
16197427 $OD junkyard TBI set-up

FSJ Guy
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Re: Jason's TBI thread

Post by FSJ Guy »

sgtpoliteness wrote:I've always thought is smelled a little rich, but that's not real accurate barometer. I'm gonna modify the DV and see how big of a difference it makes to my fuel trims.
Actually, I think it is. Mine never smelled rich when TBI'd. In this case, I think your nose knows best.
Ethan Brady

http://www.bigscaryjeep.com

Jeepless, but I still have a lots of old parts in my garage!
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sgtpoliteness
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Re: Jason's TBI thread

Post by sgtpoliteness »

Finally got around to making a slight modification to the AIR pump system and did a quick data log. It wasn't so far off that the computer can't make an adjustment now. Less fuel smell!

I have noticed a new issue. When the ambient temp starts to climb I hit almost an RPM wall. I'm wondering if the fuel pump isn't getting hot and can't deliver enough gas at WOT because that's the only time it happens. The pumps are cheap and I may just order one and install it to see what might happen.
1977 Cherokee Chief WT w/ 2" lift
360 (originally a 401)/TH400/QT w/ MM part-time
16197427 $OD junkyard TBI set-up
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sgtpoliteness
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Re: Jason's TBI thread

Post by sgtpoliteness »

Update time. So, the annoying lack of power when it's hot issue finally got bad enough for me to drop the tank and clean it again. Put new seals on the pick up and sending units and a new lower filler hose.

I hadn't gotten around to removing the glass, clean-able fuel filter (pre-pump) and it plugged up with tiny particulates causing pretty severe fuel starvation. Replaced it with a cheapy plastic one and, voila!, much better.

Made an...adjustment to the underbody a bit where I was getting an annoying drive train buzz. This, of course, only popped up after I was a good Jeep owner and replaced the sagging trans mount a couple months back.

I'm still battling the lack of power, before it's up to temp, from the AE. It bogs down if I give it a bunch of fuel, but clears up after 2 or 3 seconds and/or I let up off the gas to 50% throttle or so. But, it goes away once it's all warmed up so... :roll:

I've got a lot of minor housekeeping things to do but I'm thinking of selling it at some point and moving into a Wagoneer. With the son almost a year old, it's just to big of a pain to get him in and out of a rear facing car seat, especially when sleeping. I'd also like something with AC, for our rather warm summers. I love, love the Cherokee. It's been fun, but 4 doors would be really ideal.
1977 Cherokee Chief WT w/ 2" lift
360 (originally a 401)/TH400/QT w/ MM part-time
16197427 $OD junkyard TBI set-up

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Re: Jason's TBI thread

Post by AwesomeJ10 »

keep the cherokee and build it over time.

in the meantime, buy one of these; 95-97 lancruiser w/factor lockers. We have two of 'em here at the walden dunes. No other vehicle can withstand the severe abuse we've put these things through over the years and they are pretty cheap. saw one on craigslist the other day for 5k.

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sgtpoliteness
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Re: Jason's TBI thread

Post by sgtpoliteness »

Ah ha! I might have gotten rid of the lean bog. I increased AE MAP a week or so ago and that helped a bit. Today I made a very small adjustment to AE Temp Correction Factor. I made a few runs from cold to hot while monitoring the bog and engine temp. After isolating the problem areas, I raised the correction factor for those areas by .1 to .2. Great throttle
response all the way home, 25 minutes in 80-85 degree heat.
1977 Cherokee Chief WT w/ 2" lift
360 (originally a 401)/TH400/QT w/ MM part-time
16197427 $OD junkyard TBI set-up

FSJ Guy
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Re: Jason's TBI thread

Post by FSJ Guy »

Sweet!! There are so many tables to adjust... It's a blessing and a curse. LOL!
Ethan Brady

http://www.bigscaryjeep.com

Jeepless, but I still have a lots of old parts in my garage!

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Re: Jason's TBI thread

Post by AwesomeJ10 »

Good thread.

How are you doing Jason? I think I may have lost your number.

Any chance you have the bin file for your old setup? I'm playing around with a 7427 on my AMC 360...
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Re: Jason's TBI thread

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Blake wrote:Good thread.

How are you doing Jason? I think I may have lost your number.

Any chance you have the bin file for your old setup? I'm playing around with a 7427 on my AMC 360...
Hey Blake! I decided to take a quick look on here this morning and saw this. I think I still have your number. I'll try in a awhile and we'll chat about that file. I should still have all that.
1977 Cherokee Chief WT w/ 2" lift
360 (originally a 401)/TH400/QT w/ MM part-time
16197427 $OD junkyard TBI set-up
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