Tasks on a new purchase ZR1

[Matt B]

You could measure the resistance of all injectors as a valuable indication of their condition. There's a guide on Marc's page. Engine should be hot and stopped for about half an hour to ensure maximum heat soak in injector area.
Injectors can stay in place and only a few plugs have to be unplugged if you follow the instructions.

This is money well spent as faulty injectors can cause severe damage, e.g. damaged catalysts.

[fastpace]

Originally Posted by A26B

The common failure of injectors for 90~92 MY is due to ethanol. Most pump fuel in the US contains 10~15% ethanol blended with gasoline. The solenoid windings in the 90~92 injectors are not compatible with ethanol, which breaks down the varnish insulation, allowing short(s) in the windings. The breakdown is evidenced by low resistivity and misfires.

Cleaning does nothing for the problem. Flow testing will cost 50% or more of the cost associated with new injectors and also offers nothing in return to combat the problem. The correct solution is to replace all 16 injectors with new ones (not from GM or ACDelco old stock).

So, it's not a "just in case" but more like a matter of when, unless you are able to use only 100% gasoline.

Thanks for the detailed answer, exactly what I was looking for. Makes a lot more sense, and in that case will probably go ahead and replace them while I'm in doing everything.

So just so I have an updated running list:
Oil Change - Driven HR4 10w30 and Wix filter
Trans Fluid - Castrol Supercar 10w60
Diff Fluid - Valvoline 75w90 Synthetic + ACDelco limited slip additive
Spark Plugs - ACDelco 41-602 gapped to 0.035"
Air filter
Fuel Filter
Replace brake and master cylinder hydraulic fluid (syringe method)
Clean PCV and throttle body
Check brakes
Replace fuel injectors (16) - Intake Plenum Gaskets and feed & return block orings
Serpentine Belt
Cam cover vent filter

[Figure8it]

Since you are already there, I would consider replacing the Fuel Pressure Regulator with the updated kind from Jerry's. When I did my injectors this winter, I got everything back together and then had the FPR fail spilling fuel out the TB/airbox. It required me to take everything back apart to replace it. Get Marc's video, have some spare vacuum hose and expect to break some clips.

I had a great time, even with the setbacks, being a new owner and working on my car. Enjoy all that time you get to put into it! Congrats on your new ride!

https://www.jerrysgaskets.com/regula...re-90-95-14c3/

[Jcsws6]

From my experience, add an idler pulley and an oil pressure sensor and switch. All have failed on me when I've taken zr-1s on their first long drive.

[DRM500RUBYZR-1]

Originally Posted by Young1

Check the fuel pressure. Pull the pump unit from the tank for inspection for corrosion and rubber deterioration. Make sure battery is fresh. If older than 3 years change it. The 30 year old eletronics are finicky. If the car runs fine now and does full power fine those injectors will give you warning later. I bought quasar from original owner with 34,000 miles. Checked all fluid levels, changed nothing and left for a thousand mile trip. Get out that oil change store stuff for sure. Drive it. Run gas thru it. Have fun.

Pull that fuel pump!!!
RARELY have I found them to be rust free after 25-30 years!
If nothing else replace the sock, if all else good.

Replace or at least inspect all 4 brake hoses. Stainless are suggested.

FUEL INJECTORS!!!

Make sure hood strut has not lost its oomph before you get bonked.

Inspect rear hatch weather-strip especially in front corners, replace if torn.

Find someone with any of the aftermarket shifters and try it. Act accordingly.

As suggested earlier, new battery and add permanent battery tender connections and tender. Avoids many odd gremlins.

Add ZR-1 Net Registry decal.

Add Fuzzy Dice!

Drive; Enjoy, Repeat.


Marty

[mjszr1]

Originally Posted by fastpace

Driven is the new branding for what used to be Joe Gibbs oil. Has been regarded by many as some of the best oil on the market. Their HotRod (HR) series oils are formulated for flat tappet and older overhead cam designs with 1200+ppm zinc. It's one of those things where everyone has their own opinion on oil selection, but in the end it has the necessary ZDDP for an LT5.
...

Oh, cool, thanks for taking the time to explain. I just did the AmsOil, they had the high zinc formula locally, but will definitely look into this my next oil change, thank you!

[Z51JEFF]

Can't forget the secondary starter relay modification. From what I understand the wiring setup in 90-92 was a faulty design and allows to car to not start from time to time. My 91 did this a few times,did the mod and no more -DREADED NO START SYNDROME- On the other Forum there's a STICKY at the top of the ZR-1 page of this mod. Some have argued I've got the wiring not absolutely correct but it works for me.