Questions regarding checking cylinder compression

[XC92]

I'm going to check cylinder compression on my '92 Talon TSi AWD soon and want to make sure that I take all the proper prep steps before doing it. I've done it on other cars but never my Talon.

Here's what I'm thinking:

1. Warm up engine: How do I know it's warm enough, in terms of gauge dial?
2. Disable fuel pump & injectors: Necessary, and if so how?
3. Fully open throttle: Necessary, and if so how?
4. Crank engine: 4 or 5 turns enough?

 

[92AWDHX40]

Compression Test | DSMtuners

 

[XC92]

Thanks. I suck at searches, but eventually ended up finding a different one just as useful. I'm finding that a Google search is a lot more useful than a site search.

 

[2gmitsueclipse]

https://www.dsmtuners.com/threads/compression-and-leak-down-testing.338152/

 

[XC92]

Yeah that's the one I found.

 

[1990TSIAWDTALON]

I have found that using Google and adding DSMtuners at the end of the search request will return a pleather of results that you can browse thru.

 

[92AWDHX40]

Yep 99 percent of everything we ask for if we are unsure are on google type in dsmtuners. Not much we havent discovered over a decade ago.

 

[twicks69]

99% of the questions you have asked lately can be found out by searching here, Google with DSMTUNERS in the search query, or on http://www.vfaq.com/index-main.html

 

[XC92]

I've tried the vfaq but parts of it seem to have disappeared. Is it still active?

Anyway, I just did the compression check. '92 2.0 Turbo AWD. ~78k miles. Throttle was wide open. Pulled the MPI fusible link and turned the engine over 4-5 times for each test (and yes I zeroed the gauge before each test and made sure it was tight).

These are the numbers:

Cylinder 1: 152 (160 after squirting oil)
Cylinder 2: 154 (160)
Cylinder 1: 157 (159)
Cylinder 1: 164 (165)

These are pretty good numbers, I think, for a car this old and with these many miles, but I'm wondering why they get progressively better from 1 to 4. And the 12 psi delta from the lowest to highest is approaching the 14psi limit.

Also, the fact that squirting oil gets the numbers up indicates some ring wear, right, but is this in line with the miles on the car? Anything to worry about or look further into?

Separately, I also just replaced the air filter (K&N), plugs & wires (NGK), PCV valve (OEM), and changed the oil (Walmart 10W-30 synth, will be replaced after 100-300 miles) and filter (OEM).

I'll also be replacing the fuel filter, but only after I drop and clean the tank. It's rusty.

 

[pauleyman]

I wouldn't overthink it. Good enough for now. Get the car running and driving well, drive it hard and check it again.
Even if you didn't I wouldn't concern myself with those numbers.

 

[XC92]

Car IS running and driving well. Only thing holding me up is dry rotted tires that are unsafe to drive at speed and won't pass inspection. I placed an order a week ago but there's a delay so it'll be another week or two (I got Michelin Pilot Sport A/S 4's). Once they're installed and the car has an inspection sticker, the car's basically good to go.

Still some jobs remaining, mainly replacing the timing and drive belts, replacing the rear struts and bushings, resurfacing or replacing the flywheel, and fixing that popping out of 1st issue (which hasn't been as bad since I replaced the clutch, but it's definitely there and needs to be fixed). And some minor issues here and there like power windows jamming, bunch of dents, some more derusting and painting, droopy headliner, etc. But none of these bench the car.

After I have a decent number of miles on the car post-restoration, I'll revisit compression. I'm really looking forward to finally being able to drive and use the car again, and taking a break from all these repairs. It's been exactly 6 months since I started this project and I'm pooped. I'll get to these other jobs in the spring (so he says, but chances are that I'll get antsy and start some of them sooner, especially the windows which have been an issue for years).

And, of course, thanks a million to you and everyone else here for all the help. It would have been VASTLY harder (and more nerve-wracking) without it.