The Stupid Engine Questions Thread

[SAATR]

1990 350 Tbi, is there only one Oxygen sensor? I see the one on the driver side... some parts store spec only one for the vehicle. Is that right?

Yep, just the one upstream sensor.

 

[92c1500custom]

MISSING PLEASE HELP. 1992 c1500 350 tbi. 5k on built motor. Heddman headers; aluminum heads; custom k&n air intake; msd 6 btm ignition; tbi spacer; V-1 vortech supercharged. Starts fine misses at low rpms and cruising speeds. Put your foot in it and it misses for a sec or 2 then lights up like its running fine. It is running. rich I smell fuel all the time like its not burning it. At very high Rpms it does not miss at all. Could my fuel/air ratio be wrong? Any advice would ne greatly appreciated.

 

[DRAGGIN95]

You could definitly have a fuel mixture issues, you need to get a good qaulity wideband AF ratio gauge.

 

[missinglinc]

Does anyone know the flow rating of a stock 93' 5.7 TBI intank fuel pump and at what pressure? Doing a carb swap and some other things, would like to make sure the stocker will feed the motor plenty of fuel.

 

[hefftone]

Does anyone know the flow rating of a stock 93' 5.7 TBI intank fuel pump and at what pressure? Doing a carb swap and some other things, would like to make sure the stocker will feed the motor plenty of fuel.

The stock fuel pressure is 9-13psi, per the fuel pressure regulator which is part of the TBI. Not sure about the flow rating or Max pressure, but these pumps do have a reputation for sucking.
When you remove the TBI you lose your fuel pressure regulator. Electric pumps typically use a bypass style regulator (excess fuel & pressure squeezes through the regulator and goes back to tank.) I know that carburetors usually employed a mechanical style fuel pump. I don't know how those regulate fuel pressure.



Android/Tapatalk

 

[95C1500]

I heard that E3 Spark plugs increased power. Is that true?

 

[am92]

I heard that E3 Spark plugs increased power. Is that true?

Some people say so, IMO they're just selling snake oil to people. The spark is never going to arc simultaneously to all three ground electrodes...these trucks dont really like non-OEM parts anyway. AC Delco plugs are your best best if you're going to replace them

 

[hefftone]

Wtf is this?????

1990, 5.7 TBI.......driver side, rear of engine, slightly above the oil filter...and beside the exhaust manifold..there is something looks like a metal can. Looks to have a single male spade connector on top....looks like some antique type pressure switch. Is it oil pressure, for the gauge??? Dummy light?
Mine has no wires going to it.

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[SAATR]

It's an oil pressure switch, probably for the idiot light given the single connector. Could also be for the fuel pump cutout I suppose.

 

[DRAGGIN95]

That is an oil pressure sending unit, the first few year's of our body style had 2 sensor's and then later they were integrated in to 1 sensor under the distributor.