How many inches of vacuum stock does a TBI use?

Hook it to all ports on that throttle body. When you get to the map port just move map to a different port on the throttle body. Typical TBI motor will idle with 20-21 inches of vacuum stock. Pretty much any of the cams I recommend or have listed on the website will pull at least 17-18″ of vacuum at idle.

Is there a lift up spring on a TBI?

Spring is known to break on them. take the torq screws out of the top of the TBI and lift up regulator is in the back check spring. ill have to check that out, new idea i havent heard yet.

Can a stalling engine be intermittent driveability?

Intermittent driveability problems of any kind are always a challenge to diagnose. When a customer brings you a vehicle and complains of a stalling problem, you may not have much to go on other than their description of what’s happening and when it happens.

When to change the TBI pump in a car?

Nice thing about the Actron gauge is the hose is long enough that you can watch it while you drive. If the fuel pressure drops more than 1 psi under 8-10 seconds of full throttle the pump should be changed and dont put the stock TBI pump back in even if your engine is stock.

Why does my 1993 Chevy TBI stall at idle?

Timing is steady and not jumping all over. It is a fuel issue. The only code that ever sets is a P044, lean exhaust, and the exhaust is really lean. We have swapped PCM/PROM with a same year Suburban, no change. Both vehicles run the same as this did using the other’s PCM.

What is the TBI code on a 1990 Chevy truck?

Consult a service manual or see below for any check engine light code definitions. You can use a late 80’s or early 90’s GM TBI definition. If you have access to a scan tool use a hook up for a 1990 350 cu. in. 5.7L Chevrolet truck. For some scan tools enter VIN 10th“L” 3rd“C” 8th“K”.

How many MV does a 1993 Chevy TBI have?

Even now it seems on the lean side, but will for a while have one 02 crosscount before the 20 second lean PCM clock expires throwing it into open loop. The 02 MV hot will frequently hang down around 56 MV to 156 MV and never cross over to rich for a long time.

How to troubleshoot your TBI fuel injection system?

Troubleshooting your TBI Fuel Injection System Most of the problems encountered while installing your fuel injection system or after a time of operation are very simple. If your check engine light is on you more than likely have a hard fault meaning something is grounded out, unplugged, operating out of range or has gone bad. See

Which is a better TBI pump Vortec or TBI?

Put the 1996 Vortec EP381 pump back in. MUCH better pump than the EP386 TBI pump. Now to the too much fuel. First check the number 3 and number 4 spark plug electrodes as those cylinders always run off a different injector. The coloring should match on these plugs.

Where is the idle plug on a GM TBI?

Plug the vacuum lines with golf tees or other suitable item. Remove plug over the idle screw located on the right front of the throttle body by using a hammer to drive a punch into the plug and then using the punch to pry the plug out of the throttle body.

Is it possible to pull 1hp per cubic inch with TBI?

While TBI has a few crippling limitations it is still possible to pull a little over 1hp per cubic inch from these vehicles but requires a LOT of good planning and implementation to pull that kind of power level off and I am here to help provide that advice as well as support for the computer system to help you get there.

When did TBI chips throttle body injection start?

Welcome to TBI CHIPS throttle body injection services. So Just what is TBI, stands for Throttle Body Injection used by GM in the early 80’s through 1995. The early systems from 1982-1986 are just too old to do much with. 1987-1991 were still SLOW computers with tiny chips limiting what can be done with the system.