I just started on step 2 of the Ultimate TBI, I ground down the rims of the bore to be even with the throttle body, reinstalled the TBI, and the car runs like hell. It sputters and blows smoke for about 2 minutes, then starts to run fine. Driving around town it runs perfect, but shut the car off and restart it, then it goes back to running like hell for about 2 minutes. Is it starving for more fuel? or what. Snufilupigus FIY, I'm in Omaha.


88 Formula

 

You didn't accidently dig into the sides of the bores when you were grinding on the throttle ridges did you. If you did there may be a small enough gap for air to leak in past the blades. ALso check for vacuum leaks at the base of the TBI. High reving is a sign of vacuum leaks. What other mods do you have. You shouldn't really be lean yet. I did the ultimate mods with no problems at all.

 

I only ground down the ridges on the top, I have not ground down the shafts on the blades or screws, so the sides of the bore have not been touched. The SES light does come on, only after its starts running right. The TBI seems to be hissing much more, but there is better throttle response when driving.
After grinding down the ridges, I cleaned the TBI off the best I could, ran it under water then used a air can to dry it off and wiped out the bores with a cloth. Everything seemed to go back together right, except one of the fuel line nuts going into the TB seemed a little tough, but it went in.

 

get the code from teh computer after it pulls it and see what it is and get back to us. Should just be able to short the two uppermost righthand pins (A & B) if im not mistaken and the computer will blink the ses light to return the codes. There is a tech article covering this here. Ive never doen this b/c i always use winaldl. Its free and it works great. I suspect that you may have disconnected something by mistake.

 

teh codes will be returned as a series of blinks form the ses light. Each code will be cycled three times before it progresses to the next. An example would be the first engien not running code. "blink... blink blink..." which is the error code 12 for the enine not running.

 

It sounds like it's running like crap during open-loop, then well during closed loop. That is really strange...not sure what would cause it, but if it DOES in fact run well after 2 minutes, then you probably didn't physically damage the TBI.

How about if you shut off the car HOT, and restart - does it still take ~2 minutes? If so, then it is DEFINATELY an open/closed loop thing. But the error code(s) will tell us more.

 

hey im from omaha

Andrew

 

Hello, I got the engine code, it was 32. I think I saw something on the site about the infamous code 32. Let me know what to do?

 

its the egr code. A bad egr (exaust gas recirculation) will cause soem problems. Its the round thing on the pass. side of the engine next to the tbi on the intake. Take it off and make sure nothing is clogged and check to see that it isnt binding. Push on the underside on the diaphram (bottom of the round thing) and see if it moves freely. If not replace it. An egr that is stuck open will cause very poor idle because the engine is asperating its own exaust gasses instead of air. Probably a good idea to replace the unit if its old and coked up.

 

oh.. and check all the vacuum fittings connectiong to it and the electronic vacuum valve nearby.

 

I checked everything I could, I took the egr connection off the TB and there was suction, all connections are correct. The car ran perfect before I ground down the ridges and it only has 53,000 miles. I checked the codes again, now I am getting 23, 32, and 33. I changed the oil tonight? I am noticing black sh** and liqiud coming out of the exhaust, especially when revved up even after the idle evens out. The idle goes to normal faster with the air cleaner removed. Help, I do not know what's wrong, and car shows are coming up.

The only other thing I can think of, when I took the TBI off, some gas started coming out of the lines because I forgot to open the tank. I do not think gas went into the manifold, but just in case I changed the oil.

 

code 23 is really nothing but id recomend moveing the temperature sensor over to teh firewall somewhere and hooking it back up. The code 23 indicates that sensor is either dead or not hooked up. Its in your old air cleaner, it has a black connector and it screws into the base of the old air cleaner. Code 32 (egr) and 33 (low vacuum) are both indicative of a bad egr that is stuck open and causing the poor idle. Also, does it run ok under medium throttle? If it soes then there is definatly something wrong with the egr. Did you check the vacuum solenoid as well? The egr valve is most likely bad. You said there is a vacuum coming off the tbi but thats not necessarily indicitave of the egr working.

As for the black crap and liquid, if the liquid isnt greasy, then its water with soot mixed in with it. The poor engine performance will cause lots of sooting. You can probably take it to a shop for this one, they wont charge much to do an egr and they can diagnose your car first hand which is something all of us dont have the luxury of doing since we're in cyberspace.

P.S. Dont even mention the gas leaking out. I left my fittings off and the change in temperature forced around two gallons of gas out the tank and the fumes almost caused an explosion! Guess I should change the valve on the vent tube one of these days.

 

ill bet you forgot to reconnect the Map sensor

 

Pablo's got a good point. Check to make sure the map (manifold abs. pressure sensor) is connected. W/o the map sensor, the computer will revert to defalt fixed map value and use the tps for input instead. The map sensor is located on the firewall to the right of the heater box. Follow the vacuum line from the back of the tbi (the angle fitting there) to the sensor and make sure its connected properly.

 

Thank you for all your suggestions. It's starting to run better, code 32 is gone. I checked the MAP sensor, it was connected, I disconnected it and the car started, idled, and ran perfect. Is this a sign of a bad MAP sensor. The codes have changed to 33 and 34.

 

if it starts and runs good w/o it when the computer goes to the tps for fuel metering, then id say there is a good possibility that its bad and sending the wrong info to the computer.

 

Hey, I'm looking to mod the tbi on my 2.8l s10, can someone show me pics of what to grind down?? Or can I bore it out, and put new flaps in it??

 

you can gat a nice 400 cfm holley tbi for your s-10 if you want. Probably cost around 300. Dont bother trying to bore it out unless you have access to machining equipment. For your tbi, if you look at the top of the tbi after you remove it, the barrels will have to raised ridges on top to direct air in. Just grind those flush with the top surface of the tbi and replace the stock air cleaner with an open element. This is all covered in the tech articles so go there and you can read all about it. Happy modding, Dale

PS heres a good link with a few pics.

 

88 LO3's don't have a MAP sensor...

 

mine has one

 

You are wrong.

 

As I recall LO3's have a MAF sensor...

 

Not MAF and MAP sensor...my 88 lo3 has it..right above the heater box like everyone elses.

 

maf "mass air flow" for air forced induction cars like TPI... TBI cars have a MAP sensor since we dont have your typical fuel injection and "forced" air flow just an air cleaner.

 

ok i'm starting in on the porting mod, after i took off my TBI i noticed oil/fuel mixture between the TBI gasket and the manifold, i suspect this isnt good but there isnt any sign of oil in the intake, but when i took off the injector pod, in the locating stud hole was a significant amount of oil, as well. i cant think of any way that oil could get to the TBI, except the PCV valve.

 

I have this same problem with the oil in the TBI and was wondering how it got there. Any advice would be great.

 

i was told it might be old gas and the PVC valve allows some oil in.
since tbi is wet system thats probably the cause.