1997 Sunfire 4 spd automatic repair & modding

[Daox]

Another thing I noticed on the trip in. The car likes to run on the warm side. The SG shows it sitting at ~200F once warmed up. Is this normal?

[backpacker3]

I haven't noticed mine running hot but I have the Ecotec you should have 2.2 ohv right? Honestly I'm not that familiar with that engine but since Eco swapping (switching the ohv for the Ecotec) is pretty common I thought would check.

[Daox]

Nah, its the older 2.2 before the ecotec.

Well, a few miles with a scangauge will tell you a lot!

1) 45 mph and locked trans is WAY better than 40 mph unlocked. We're talking ~15% increase in FE. This just reinforces the thought that locking the trans is super important.

2) The trans will stay locked at engine loads up to at least 80%. This means accelerating with the trans locked is totally doable. Clutches care about torque, not horsepower.

3) It actually runs about 210F when fully warmed up. I might want to look into this to see if there are any issues. This seems very warm. I want to make sure the radiator fan isn't kicking on a ton to keep things cool.

4) Neutral idle consumption is about .36 gph. Keeping it in drive while not moving is .39 gph. So, there is about an 8% fuel consumption reduction from shifting to neutral at stop lights.

5) P&G with neutral coasting at in town speeds 25-35 mph is effective.

6) Its still not that easy to top out a heck of a lot more than 30 mpg.

Mpg in to work this morning was 31.6 mpg, a significant jump (thank you scangauge!) since yesterday (27.2) with nearly identical weather. Ambient temps were mid 30F.

[Daox]

The last couple mornings I've taken the car to work it has started fine, but idled a little rough at start up. The mechanic who did the alignment also mentioned this when I picked up the car. The car has had the check engine light on for a few months for a small evap leak, so I didn't think to check it. Well, I got around to that the other day to see not one, but four engine codes. One was still the evap leak, the next was a problem with the crankshaft position sensor, and the other was the camshaft position sensor, the 4th was an unknown code. Obviously this is going to effect my ignition timing and thus efficiency, so I need to figure out what is going on there.

On the plus side, I've been getting more used to the car. I've been doing more neutral coasting with it. Today was a nice warmer day, almost 60F! I got 34 mpg on the way in to work. So, unless the SG is really far off, I should fairly easily be able to hit my goal of 30+ as a tank average. The SG currently says the tank is at 29.9 mpg.

[MetroMPG]

I hope it's not off! My brother's new truck was off by over 30%!

That was a bit discouraging to discover on the first fill.

[Daox]

We shall see in a couple weeks. I only have about 100 miles on the tank.

[backpacker3]

Just as a question has this car had spark plugs, belts, oil change, new filters etc. done? My sunfire was at 105k and change when I got it and the full maint I did got about 2 mpg extra for me just as a suggestion I'm still considering doing sea foam in the gas to see what that does.

[Daox]

I did dump some seafoam into the tank last week after I filled up. I think I looked at the plugs and made sure the gap was good. They looked light tan like they should be. I should probably double check that now that its been driven for 6 months or so. I looked at the belt the other day. It has some cracking. I'm sure its due for an oil change too.

[pgfpro]

Sounds like your on the right track.



One thing I would like to see is more people trying John Deer Hy-Gard gear transmission and hydraulic oil part# TY6354. I have been using this in all my race transmission for about ten years now. It lowers stall speed by as much as 800 rpm. Also reduces torque converter slippage on the big end.
On my testing I seen a 3 mpg increase. You can actually feel the torque converter tighten up. It also handles heat way better then anything out there. On our 7 second Camaro we could run a whole season with out any maintenance running Hy-Gard with all the other transmission fluids it would require maintenance about mid-season.

Now with this said use at your own risk.

[Daox]

Have you done a before/after oil analysis to see what is going on with this oil?