240SX "the Blue Ghost"

In reply to noddaz:

Well after a few days of driving it and never having a temp problem, I opened the radiator and added some more fluid. Hardly any was missing so if there's a crack it must be tiny. I've squeezed the hose, but really don't see it leaking anywhere.

There's always a little bit of fluid on the top left corner of the radiator were the hose goes in.

So I think the overflow tank is the next fix. Then some tires and brake pads.

I'm running crappy yokohama all seasons right now. They're brand new so it was good deal when I bought the car, but they aren't going to cut it for autox.

I plan on driving the car to events so I'm trying to decide whether I want a dedicated set and change out or if I want to find some streetable autox tires and brake pads.

Radiator is SUPER easy, especially since it's a manual. With no experience like you say you have I bet you can still do it in under an hour. It's probably leaking where the plastic meets the aluminum-pretty common, not unusual at all. I say do a few autocrosses on the tires you have, learn the car, then upgrade. At least that's what everyone on here tells me when I ask...I'm a newb too! Good luck!

The radiator leak is getting a bit worse. I can see bubbles at the crack when I squeeze the hose. I went ahead and ordered a CX Aluminum Racing Radiator and new hoses.

Ought to be a decent upgrade of stock plastic tank radiator and you can't beat the price.

I'll post some pics of the install once I get it. I'm excited to get my hands dirty!

Some more pics after I applied the required GRM stickers to the side for an HP gain.

South of the Border sticker on the rear because why not.

Aluminum radiator tank, coolant reservoir and hoses on the way.

Over the weekend I got the old radiator pulled out and the thermostat replaced. This was my first experience doing anything besides changing oil.

Draining the radiator and removing the hoses was simple. I took pictures so I'd know where everything goes and baggied/labeled any loose parts I took off.

Removing the radiator was not difficult but I got frustrated/impatient when I couldn't get the old radiator to come loose from the lower fan shroud. I pulled a little too hard and cracked the fan shroud a little, but it's still in one piece. I felt silly because all I needed to do was get under the car and pull the radiator and fan shroud apart from one another and the radiator lifted right out. I gotta work on taking things slowly.

Still waiting on the new radiator and hoses. Though the original hoses are still in pretty good shape.

The thermostat was a huge PITA. The coolant neck is right behind the clutch fan. I didn't want to remove the fan so I worked around it. Old thermostat removal was easy but replacement was a pain! You have to place the thermostat into the block, then in one smooth swoop perfectly place the coolant neck with the gasket back onto the block and not disturb the thermostat. Next time I'm going to use liquid gasket. I read either will work.

I guess I won't know if I did everything correctly until I hook it all back up, but I'm pretty satisfied with what I've accomplished so far.

Good work! The best way to learn is to just do it! You'll make mistakes, but just take them in stride and learn from them. Have fun!

New radiator, overflow tank and hoses came in.

Radiator dropped right in.

The new bottom hose went on without an issue, but the new top hose needed to be shortened a bit. Of course I wound up shortening it too much and had to use the original hose that was on when I bought the car, but it still looks like it's in good shape. Easier to replace it than the bottom.

The biggest pain was the plastic clutch fan shroud. The two halves just clip together and it's been cracked over the years.

I got everything back together, filled up cooling system, cranked up and ran heat full blast to bleed air. No hot air and after a few minutes I was close to overheating.

It turns out the engine likes to trap air easily so I used the bleeder bolt to bleed air and added more fluid as needed. Had hot air coming out the heater in no time.

I've driven the car around since Saturday and so far the coolant level is fine and the temp gauge hasn't moved a bit!

Bonus, my class magnets came in from soloperformance.com

Went for a joy ride yesterday. Car ran great, temps were great.

I had to run back out to the store later on and I on the way out of the parking lot the car starts bucking whenever I try to accelerate. Like it's almost out of gas. It usually happens around 3k rpms regardless of what gear your in.

Car still cranks right up, idles fine and engine sounds strong when you rev in neutral.

Thoughts I've had:

*There should still be plenty of gas in the tank. The gauge worked when I got it and it's a little under half a tank. That doesn't mean the gauge isn't broken now, so I'm going to put a little gas in to see if any change.

*The CAI is sitting right on the radiator. It was so hot I couldn't touch it when I opened the hood. Maybe I need to make some sort of spacer? Would this matter?

*When replacing the radiator I had to take the intake off. Maybe one of the hoses going into the intake is pinched? Maybe after driving around one of the vacuum hoses got bumped loose?

*I wonder if it's the MAF? I'm not getting an MIL though.It'd give an MIL if it was. I have no reason to believe ECU isn't working.

*I do have EGR valves. Blockage?

*Dirty fuel filter? Bad fuel pump? Replacing the fuel filter is no biggy, but I'd rather troubleshoot elsewhere before buying a new pump.

There's just so many things it could be I don't know where to start.

Any tips on where to start trouble shooting? I've checked the usual forums and I've read of similar issues, but no consensus on where to start

Stuttering at 3k rpm is most likely the MAF. It's a common problem on the 240s. Probably not a bad idea to replace the fuel filter too. Get one from a 300zxTT. It flows better and has more filter material in it. :)

I was thinking MAF too, but I wasn't getting a MIL and I could rev past 2500k while idle.

I replaced the fuel filter and went for a long joy ride and not only did throttle response feel better the entire ride felt better.

I didn't know about the 300zx filter, thanks! I just went with a 240 one.

I'm learning a lot from all this! After an oil change I think it might be up to an auto-x at the end of the month. Almost a 3 hour drive, but I'm confident (and have AAA lol).

The stuttering/bucking when over 3K has returned! I got it home and in the garage, it was still running and in neutral I could rev over 3K.

Killed the engine and checked all my various hoses etc. under the hood. Everything looks OK.

Cranked it back up and the revs are jumping from 300-1000K and the engine almost dies.

It could be the MAF.

Update: I unplugged the maf. Revs are still jumping, but with the maf unplugged I can't rev past 2500k at ALL unlike my original issues where I could get around 3k while driving before stuttering began.

I also noticed that before when I've undone the gas cap I'd get a "PSHHOOO" sound as pressure released. Which is normal apparently. I no longer get that at all.

...and it's ALIVEEEE! (again) Changed spark plugs, new wires will be done tomorrow. New fuel cap, because I don't think the stock one was holding pressure.

Still had funky idle issue. I took the intake back out and cleaned up the vacuum hoses. Tightened all my clamps. Did a better job of arranging everything when I put the intake back in. Intake isn't as close to the radiator as it was.

Now it cranks and idles much better. There is still a small fluctuation, but it's not bouncing all over the place. Took it out and it ran great. Drove it to work this morning as well.

Well this weekend will be the 240's first AutoX and it's about 3 hours away.

Kind of nervous since it's such a high mileage car. It's at 189,5xx right now, but I've been taking care of basic maintenance and replacing what needs to be replaced:

Fancy new NGK plugs, NGK wires, CX Racing aluminum radiator and CX Racing overflow tank.

New fuel filter, Oil changed. 3 qts of Castrol 10w40 and 1 qt of Lucas Oil Stabilizer. No smoke.

No temp issues, no coolant leaks, no oil leaks, no leaks of any kind and my fluid levels are good.

Full tank of 93 octane. Extra oil, water, coolant and toolbox in the trunk and my AAA card in my wallet.

I think she's ready to roll.

With so much cash restraint, mine is still sitting in the barn waiting for a body swap. Yes, body swap. The engine is great, bu the body is crap.

Sounds like you're ready to go! Have fun!

Very nice, looking forward to hearing how the Autocross went! Very nice to see another 240SX done up right.

The 240sx made it to the Auto-X with no issues! It was a really small course in a really busy parking lot, but they did the best they could.

5 runs. 40.807/42.579/42.301/39.956 + 1/38.907. So my total was 38.907 + 4.013. Here are some pics:

Not great quality on these:

Mileage after the round trip/autox, not one complaint from the car, in fact I swear it felt better afterwards. It'd been parked for almost a year when I bought it:

And finally here's a video of my best run

Next one is at the end of October. It's closer and going to be a BIG course at Michelin's Proving Grounds in Laurens, SC. We get the entire "black lake" which is 1400ft x 400ft of perfectly smooth asphalt.