tune up ?

[stizkidz]

I have been in the process of giving the tbi 350 in my 88 K5 a tune up. So far I have changed the oil, oil filter, fuel filter, air filter, cleaned the tb and pcv valve with spray cleaner, put lucas fuel system cleaner in the tank, used a bottle of gm top engine cleaner, topped off all fluids, and changed the spark plugs and wires. What else is there to do? Any suggestions to complete my "full" tune up? /forums/images/graemlins/confused.gif

Also, my oil pressure guage is always reading zero with no movement at any time of the needle. I tried taking the instrument cluster cover off today to see if the contacts on the guage were corroded but I cannot get the cover to come past the clock set button and tripometer reset button. I do not want to break them off but how do I remove them to take the cover off? Also, how can I tell if the oil pressure sending unit is bad or if the guage itself is bad? /forums/images/graemlins/1zhelp.gif

Also, a few questions about the emissions system: I noticed that there is a heat tube from the manifold to the air cleaner. Does this serve any purpose, because I am considering putting on an aftermarket open-air cleaner? I also want to know how necessary the smog pump is? If I remove it, what are the chances of failing emissions at inspection (as long as my CAT is in working order)? /forums/images/graemlins/crazy.gif

 

[James670X]

Why not put a new pcv valve in it instead of just cleaning it?. Other "full" tune up items you've missed, replace distributor cap and rotor, fuel filter, crankcase filter (should be inside air cleaner housing), oxygen sensor, check engine timing.
As for the oil pressure gauge I can't really help you there.
The heat tube from the air cleaner housing to the exhaust helps with cold starting/warm up that's all.

 

[diesel4me]

You can test to see if its the oil gauge or the sender by grounding the wire to the oil pressure sending unit for a few seconds with the key "on" and engine off-(if your getting no reading at all,the wire might be dissconnected!)-if the gauge is good this will make the needle peg out at maximum--dont leave it grounded for too long or it might damage the gauge.Or you could just buy a new sending unit and try it--they arent that much money--they will likely ask you the type of gauge you have,how many PSI it says on the dial,to get the right one.Its located next to the distributor,a pain to get at--some newer trucks have it down near the oil filter,but there is another oil switch for the computer(if your truck has one)down there on some years that has nothing to do with the gauge,if you have one next to the distributor its most likely the one that runs the gauge.If you have an electric choke,there will be two switches there--the one with one wire is the oil pressure switch,usually its a brown or tan wire .
That "hot air" tinfoil hose thing sends heated air to the carb to prevent carb icing and hesitation and stalling when its cool out(below 50 degrees)--I like having one that works,having an edelbrock carb with a spacer that runs so cold it looks like a frosty mug most mornings,and is very annoying to keep running until it finally warms up completely.Many people ditch it,and the stock air cleaner setup when they put an aftermarket carb on--I have no trouble in the summer months,but most of the fall,winter and spring we get lots of foggy rainy cool weather my edelbrock despises--it runs like crap until you run it 20 minites or more,sometimes it never warms up enough,and you must drive with one foot on the gas,and the other on the brake to keep it from stalling at stop lights.You may or may not notice yours missing--mine is very fussy about the weather.As for the air pump,I have still passed the emission test without one,or one that is disconnected,but the motor has to be in good shape and tune--if its missing you could fail the "visual"inspection--if its supposed to have one and its not there,they might make you get and install one--around here its how anal the inspector is rather than the laws that determine what you can do without,and what absolutely needs to be there.It helps to know someone at the inspection bay! /forums/images/graemlins/whistling.gif

 

[stizkidz]

Can I bypass the smog pump pulley and just leave the equipment in place? If so, this won't adversely affect anything engine-wise, right?

 

[Thunder]

Dont put a open element air filter on a TBI truck you will only loose power. TBI needs the cold air from the front of the engine. The stock air cleaner and tube flows plenty of air for TBI. Just put in a K&N filter.
Smog pumps really dont hurt performance. If it is working correctly just leave it on. You wont gain much by taking it off. Dont know what the smog inspections are like where you live but if the sticker under the hood says the truck is susposed to be equipited with a smog pump. And you yank it, it will fail a visual inspection.
Smog pumps on FId engines only work when the engine is cold after they warm up it goes into bypass.