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TBI Mods:Snake oil or worthwhile??? Updated 5/19/12 AFPR and Pod Spacer!!!

I finally got my estimate for a total repaint on my blazer... $2500 with fixing a couple rust spots, fixing a crease down the passenger side from the PO, and painting the top. This is for a full repaint door jams, dash, interior, everything... He's a young guy from my church that just opened his own shop doing custom work on harleys, Honda civics, and volkswagons... He said it will take about a month to finish it, because he's got to keep doing fender repairs etc. While working on mine to keep paying the bills. Hopefully he doesn't bail on me like the last guy... My only other option is maaco, and I just can't bring myself to let them touch it. Now to get the $$$ together.
 
I thought so, and I've seen a few cars he's done, plus I'm friends with his dad. Now to make up my mind on what to paint it...
 
You're not kidding, I flip flop back and forth on color choices... I may just let my 7 year old son decide!!! Maybe someday this thing will be his!!!
Back to the original subject, I'm sitting at lunch thinking about the throttle body spacer and my suspected lean condition/fuel delivery issue. Just like everything else on this truck, everything I've done so far seems to help the problem, or in this case, I think it has inadvertently covered up the issue. I haven't noticed any of my erratic pinging since the throttle body spacer was installed. I've read about the benefits of flow matching injectors, and I'm wondering if some of my issue hasn't been a dirty or poorly flowing injector that the spacer is now allowing fuel and air mixture to cross over and equalize? I'm starting to think it may be time to get my injectors cleaned and checked/possibly replaced while I'm at it? Thoughts? Spray pattern looks good, but that doesn't necessarily mean much, and yes, in case you're wondering, I'm a bit of a perfectionist/obsessive compulsive...
 
Years ago my buddy got the flow injectors checked/rebuilt on a 4cyl Toyota pickup he had. Wasn't a power house to begin with but it ran well enough for him. Just had a few nagging issues and he had chased everything else.

His was a MPI setup but the variance between the 4 injectors was crazy. One was dribbling fuel while another was pulsing and only two were working somewhat normal. Couple hundred worth of rebuilding later it ran great.
Can't hurt.
 
Get a chip from Brian Harris.... It did WONDERS for my K5!!!

I went from 87 fuel, to 91 Octane.
I also went from 8-10mpg, to 12-14mpg. (easy.)
Paired w/ an MSD Ign., Dizzy, Coil, and Wires, I gained a TON of low-end!

It's like the 350 came alive again!
...

I also run a slightly higher duration cam,
couldn't tell you which cam, tho... PO had it installed.

You can only tell it has a more aggressive cam, when you get on the trottle....
Or, after wheeling for about 2hr's.... Cuz it starts to actually "Cam".
 
More updates to come, I'm in the process of getting this thing ready to drive 1300 miles each way to New Orleans and back. I'm going to be filling in for Crisis Response staff that have been pulled to Alabama and Joplin, Mo after the tornado's... So I've been distracted with fixing my AC and reinstalling sound deadener and insulation in the cab to cut the heat radiating up from my exhaust and cat. High flow cat and new flowmaster exhaust goes on this week, and the adjustable fuel pressure regulator, fuel pressure guage, and pod spacer will hopefully be installed this weekend. I've been running this thing a lot around town and I've been consistently getting 15 to 17 mpg, which is the same as before I put the TBI spacer on, but it has a noticeable improvement in power, no more pinging, and I'm back to running 87 octane!!!
 
I've contemplated a chip, but I'll probably wait until I do some motor upgrades down the road.
 
smier said:
More updates to come, I'm in the process of getting this thing ready to drive 1300 miles each way to New Orleans and back. I'm going to be filling in for Crisis Response staff that have been pulled to Alabama and Joplin, Mo after the tornado's... So I've been distracted with fixing my AC and reinstalling sound deadener and insulation in the cab to cut the heat radiating up from my exhaust and cat. High flow cat and new flowmaster exhaust goes on this week, and the adjustable fuel pressure regulator, fuel pressure guage, and pod spacer will hopefully be installed this weekend. I've been running this thing a lot around town and I've been consistently getting 15 to 17 mpg, which is the same as before I put the TBI spacer on, but it has a noticeable improvement in power, no more pinging, and I'm back to running 87 octane!!!
Click to expand...

Good to hear you noticed a power gain. I think on Wednesday I will be ordering the whole package minus the bored out Throttle body, that may come down the road though. For about $300 I think it is worth a shot and I haven't really heard anything negative about it, just hoping it will wake up my 91 burb. The motor is completely stock and it is a little gutless.
I'm just turning my burb into my camper pulling rig and hoping it will tow my 20' camper a little better than my 06 Tacoma. I'll update when its all installed.
 
I strongly believe that many of the complaints and problems that people have with these TBI setups is partly due to the fact that the OBD system can adapt and adjust, even when there is a problem, thereby covering up the issues... My truck had a massive vacuum leak at the intake manifold gasket, a sticking EGR valve, and an Idle Air Control that wasn't functioning properly... But it still ran really good!!! good enough that most guys on here probably would have bought it, and many wouldn't have noticed many of the issues. I think one of the best things anyone can do to the TBI setup is pull it off, clean it, and put a rebuild kit (all new gaskets, O-rings, and screens in the injectors), I was amazed at how gummed up mine was. I think that a lot of the problems guys have with these setups is that they worked so well for so long that no one has ever really had to mess with them or maintain them. Most of my issues were due to the fact that many of the gaskets, seals, and O-rings have just outlived their lifespan and started to fail. My truck was a totally different beast after I rebuilt the TBI and fixed the intake manifold leak!!! That was also when I gained my MPG's back... In the past year I figure I saved 363 gallons of fuel at least, 363 x $3 a gallon has more than payed for all the parts I've been throwing at this truck in the past year.
 
Nice to read on the improvements one by one. Did the spacer come with fuel line spacers as well?
As soon as the eagle drops the morning of the 16th i am ordering a bunch of stuff for the ole 79 that has been ignored in the driveway all winter. Tomorrow is the start of the harness swap....gutting the 79 harness in favor of a 91 harness...complete head light to tail light. The 91 doors are on (always wanted power doors and mirrors froma 91...)...the drivers side needs an adjustment bad! But once the dash is gutted accessing the inside bolt will be a lot easier...
Going to deleate the problematic R4 a/c compressor in favor of a Sanden SD508 with some adapter brackets. I have swapped in a fan from a 03ish tahoe (11 blades) with a 91 V30 BBC fan clutch...can't wait to hear that baby roar. Still playing with condensor ideas...i'll let ya know where that ends up.

DW
 
smier said:
I strongly believe that many of the complaints and problems that people have with these TBI setups is partly due to the fact that the OBD system can adapt and adjust, even when there is a problem, thereby covering up the issues... My truck had a massive vacuum leak at the intake manifold gasket, a sticking EGR valve, and an Idle Air Control that wasn't functioning properly... But it still ran really good!!! good enough that most guys on here probably would have bought it, and many wouldn't have noticed many of the issues. I think one of the best things anyone can do to the TBI setup is pull it off, clean it, and put a rebuild kit (all new gaskets, O-rings, and screens in the injectors), I was amazed at how gummed up mine was. I think that a lot of the problems guys have with these setups is that they worked so well for so long that no one has ever really had to mess with them or maintain them. Most of my issues were due to the fact that many of the gaskets, seals, and O-rings have just outlived their lifespan and started to fail. My truck was a totally different beast after I rebuilt the TBI and fixed the intake manifold leak!!! That was also when I gained my MPG's back... In the past year I figure I saved 363 gallons of fuel at least, 363 x $3 a gallon has more than payed for all the parts I've been throwing at this truck in the past year.
Click to expand...

You made some good point. Maybe I should slow down and just rebuild the TBI first and see if it runs better. She runs a little ruff at idle plus it has about 187,000 on it and I've only had it for a few months so I'm still getting to know it.

What TBI rebuild kit do you guys recommend :dunno:
 
Almost any parts store should stock it, get one with the diaphragm for the fuel pressure regulator. Should be around $50 for the kit, and you'll need several cans of throttle body cleaner and a drip pan. I used some brushes and a lot of rags to help clean it up. You're going to open the box and wonder what you got yourself into, but it's not as bad as it looks!!! Just study the instructions and the diagram before you get started. Mine took me between 2 and 3 hours, but I really took my time. Just really pay close attention where all the little Orings and screens go as you're tearing it apart. It's a good time to clean and check some of the sensors like th IAC and see if your throttle position sensor is moving freely.
 
Good to hear about the spacer. I have a phenolic 2 hole spacer from trans dapt on now. I believe i'll be buying the one from cfm tech later with the T.D. fuel line extensions.
I think I need to replace my IAC and EGR too, I have a slight stumble on acceleration from a stop.
My fuel mileage is about 12.5 - 13 MPG back and fourth to work.
Keep up the good work.
 
Ok guys, I'm going to pull off my throttle body tonight and go through it. One question first though. On Oreilly's web site there is a fuel pressure regulator listed with new parts for $44 and a TBI kit for $23. What is the major difference? Is the regulator adjustable? This is my first time tearing into a TBI so go easy.

Here are the links: Regulator and TBI Kit.
 
Looks like the TBI kit has the regulator kit in it already... Not sure why the kit is cheaper than the regulator kit... No the regulator is not an adjustable unit.
 
That is what confused me. Half the price for the full kit and twice the parts??? I'll have them pull both kits tonight to see what the difference is.
 
I ordered the goodies from CFM tech this morning. Hopefully they will be here by Friday so I can rebuild my TBI and add all the stuff from them. Figured I was going to get them anyway and might as well do it when the throttle body is off. I'll post my results this weekend.
 
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