Thanks in advance!

1989 Roadster with L98 and 35,000 miles. Issue (1): Since my ownership, the car would never start with "authority". It would always kind of rumble to life then settle into a relatively smooth idle. I just removed the throttle body and serviced it (cleaned), cleaned the MAF and installed a new IAC valve. I put everything back together and before starting the car, I inserted the paperclip in the OBD and verified that there were no codes (I got 1-2 three times and then 1-2 three times again). I did not start the engine, but the cooling fans came on? That's my first question/issue. Anything I should be concerned about? I did NOT disconnect the battery until after I had removed the MAF as I just forgot.

I can't start the car yet because of issue (2): When I was reinstalling the throttle body, I had left the two upper bolts in their bores so I could start threading them while the gasket was hanging on the first couple of threads and they both slipped out while I was trying to maneuver the TB into place. I found one under the car, but the other is presumably sitting somewhere in the pan underneath or near the front crossmember. I have bought replacement bolts, but I'm kind of afraid to start the motor in the event the bolt is in a bad spot. I've looked a well as I can with a couple of flashlights and have poked around with my long magnet, but no luck so far.

Lastly, I had to remove the cooling lines to the throttle body and lost a little bit of coolant. Do I need to purge the system now? What's the best way if so - just run the motor with the cap off like the good old days?

 

I'm not sure what starting with authority means but with the low miles you need to "drive it like you stole it" or drive it in second and allow the higher rpm blow deposits out of the combustion chamber.
the missing bolt most likely did not fall into the plenum. Since it was on the outside of the throttle body. You could disassemble intake removing plenum and runners. If bolt bolt fell.in it should be in ithe runners of ntake base. Magnet should reach it. If still worried a borescope could be used to look in lower runner all the way to intake valve. Spark plugs could be removed to look in chambers.
Coolant old fashion way will work. Fill radiator and coolant reservoir and drive a few miles until at operating temperature. Punch and coast works well. Then park and let sit for say 1 hour and recheck reservoir and add as necessary.

 

So - with respect to the way the car starts - it sounds like you feel the cranking speed is a little slow.

I'd suggest seeing if you can find another L98 car and compare them.... If you still think your cranking speed is low - I'd suggest checking the voltage while cranking. First check the voltage while cranking at the battery, then check voltage drop between the battery positive and the starter motor pos terminal (while cranking) and then the voltage drop between the starter motor case and the neg terminal. I'd say anything more than a half a volt of drop is N/G.

Slow cranking speed is typically a weak battery or a voltage drop between the battery and the starter motor (and the voltage drop could be on either the pos side or the neg side). .

If all else fails - you could replace your stater with an aftermarket "gear reduction" starter - designed for a SBC. Clearance may be an issue - but some of the aftermarket starters are "clockable".

 

QUOTE=Kevova;1603657345]I'm not sure what starting with authority means but with the low miles you need to "drive it like you stole it" or drive it in second and allow the higher rpm blow deposits out of the combustion chamber.
the missing bolt most likely did not fall into the plenum. Since it was on the outside of the throttle body. You could disassemble intake removing plenum and runners. If bolt bolt fell.in it should be in ithe runners of ntake base. Magnet should reach it. If still worried a borescope could be used to look in lower runner all the way to intake valve. Spark plugs could be removed to look in chambers.
Coolant old fashion way will work. Fill radiator and coolant reservoir and drive a few miles until at operating temperature. Punch and coast works well. Then park and let sit for say 1 hour and recheck reservoir and add as necessary.[/QUOTE]

Thanks for the feedback. Regarding how it starts, it just has seemed like it took a couple of seconds for all cylinders to catch before smoothing out. I’ve had carbureted cars that seem to start and catch better than the L98. We’ll see how she acts with the new IAC. I should also probably check my TPS with a multi meter. I drive the car pretty aggressively, so there’s little chance of carbon build up. I’ll keep fishing for the bolt, but it fell forward so it’s somewhere toward the front of the engine. It’s 3” long so it shouldn’t be too hard to find. I just don’t have a ton of space to move around it in my garage at the moment and I didn’t want to run it without all 4 bolts in the throttle body. I got replacements yesterday so it’ll be back together later today. Any idea why the cooling fans would come on when I turned the key to “on” to check codes?

 

Thanks for the feedback. Starting speed seems fine, it just “rumbles” to life like it takes a couple of seconds for all cylinders to catch versus all 8 firing off. Nothing too dramatic, but I’ve also never owned an L98 before, so maybe it’s normal. Still not sure why the cooling fans came on after turning the key to “on” to check codes though. If you have any ideas, I appreciate them. Maybe just standard practice after unhooking the battery until the computer resets or something.

 

If you had the AC set to on when you had to key on that would cause the fans to activate. Putting the car in to diagnostic mode also triggers the cooling fan.

 

I would clean and charge your Battery first and then clean the posts AND the connections at the Starter Motor. Then I would check the grounds and if your car still doesn't crank with "Authority" then you might consider a new Gear Drive starter as Purple92 suggested. The Gear drive starters are better at spinning the motor a bit faster. There are a lot of ground straps and battery connections that can get corroded.

You mentioned replacing the IAC, I hope that you got the matching one like the one that came with your throttle body. I learned that there were different pintles based on which year it was made. The wrong Pintle will make the IAC not work properly.

 

That makes sense. Climate control was on, so problem solved.

 

I only held them up side by side and they darn sure “looked” right. Will find out soon.

 

It looks like everyone has already given you good advice on all of your issues. For the starting with authority thing. It sounds like you are used to old school carb cars that will start with the first touch of the key. I have 3 L98 cars that I work with and on and they all take several revolutions before they will start. The L98 has an oil pressure switch that has to see pressure to keep the fuel pump running. I suspect that has something to do with the cranking time needed.

 

You might want to check fuel pressure. It could be that your fuel pressure regulator is releasing pressure a bit, and it's taking a second for the fuel pump to get the pressure back up to where it should be whwn you crank it over.

As for the fan - could be that the car was in an A/C mode (either A/C or defrost), or if the car thought it was in a limp home mode - even for a moment - it will turn the fan on (and do bunch of other stuff like pulling timing) to help protect things.

 

Please listen to Purple92 and check you fuel pressure. See what it is with just key on and see how fast it bleeds down. Check while running. Can borrow a gauge for free from chain stores. Dan PS: I have seen the oil pressure switch discussed and argued about many times. As for my 96 it starts immediately WAY before I have cranked it enough to have any oil pressure.