KA24DE seems very sluggish, and flat on power

[lancefloyd]

I just bought a 91 5 speed hatchback that has 180,000 miles (don't worry, I got a decent deal I think!), and while I've been driving it for a few days to get around town, I've noticed that its performance in the bottom end is excellent with good response and pickup, the midrange and corrensponding top end is absolutely gutless. So bad, in fact, that I tested (err...raced) my 240 against my Stanza (same engine but no "D")...sadly the Stanza won...by at least a car length! I've had the KA24E engine in both my Stanza, and my late pickup, and I know that the engine is not about scorching fast rpms or anything like that, but with this car it seems like something is plugged up or whatnot.

What is the usual stuff to check for to ensure normal performance on these cars, and what do you do to enhance the potential of this motor besides intake and exhaust?

Also, any particular intakes or exhaust that are better suited towards 240's?

Lastly, what if any simple mods have been found to improve mid and top end performance in relation to timing, tuning, etc.?

The Stanza simply has a K&N filter in the stock box, so I know it is not because I've "modded" that car!

Thanks!

[14.5drift]

Hmmm, have you done compression check, or leak down?

[thundachiken]

With mileage that high, I would suspect the cat.

[240sxJay]

What kind of service have you done, doing a complete maintenace on your car will show INSANE amount of hp that was probably lost on a high mileage car, things to do to improve performance:

-Spark plugs (ngk only: I bought Bosch Platnium, big mistake!)-Fuel Filter-Fuel pump-Belts-Plug wires-Distributor cap and rotor-Clean those fuel injectors!-Radiator Flush-Check water pump-Air filter (or install intake)-Check your hoses for leaks

After you've done all those you should see a nice improvement, maybe you've done most of what i've mentioned but maybe there is one or two things u forgot.

[lancefloyd]

OOH. well..i was really hoping not to have to replace or repair the engine! I'll try that I supppose.

Pretend for that the engine's compression was ok...what else could be causing such a loss of power? Timing? Any vaccuum leaks known to cause this? I just don't know where to start with this one. I'm going to replace the spark plugs, wires, dist. cap, rotor, etc. tonight...what else is there?

[jrc90240sx]

If the Cat is backup it could cause enough flow problems at high RPMs to drop power off. you could pull the cat out and see what it looks like if it is blocked up or not.

What fuel type are you running? maybe its pinging up top and pulls timing.

[14.5drift]

clutch could be slipping

does it feel like the rpms's are going but the car isn't?

[lancefloyd]

The cat is on my short-list of things to go bad...I will pick one out asap and replace...(maybe the evil test pipe...)

the clutch isn't exactly super strong (as evidenced by the 2-3 and 3-4 upshift at redline) but the car is not struggling against the clutch during acceleration. The tach itself looks like it doesn't want to sweep fast enough.

So...the CAT, vac. lines, add 91 octane, new Cold Air, new Cat-Back, spark plugs, wires, rotor, cap...

the car runs ice cold, so i doubt the radiator or water pump need attention at this time, but I will check them. I will definitely need to look at the injectors, ...but how do you clean them w/o sending them someplace? Dip them in something?

[HailtotheSilvia]

man, I have a 92 with 125k miles with exact same problem until I change my fuel pump yesterday (Walbro). The fuel pump definitely fix the problem for me....

[lancefloyd]

I'm happy to report that changing plugs, wires, dist. cap, rotor, and having the cat and undercar piping redone did the trick nicely. Also, because I will always use 92 octane, I went ahead and adjusted the base timing up a few degrees (no idea how much, since my timing light broke)...but it runs MUCH better. Now, I must figure out how to get more power safely...

BTW I still would like to clean the injectors, any advice on how to go about this w/o having them cleaned professionally? (might as well replace them b/c nobody does that kind of cool stuff here in the great state of KS)

[240sxJay]

There are two ways I know of how you can do this. a) go to one of those stores that will offer to clean your injectors for about 70.00 bucks, what they will do is flush it with some nasty chemical that would probably peal off the paint of your car :P

or b) You can actually take them to a professional (i know u dont' want too but it's worth it) and they put it through a machine to tell you how they are, not only does it clean it but tells u if they need to be replaced, that is around 100 bucks.... i'm not sure if you can do it yourself...

I knew if you did all those minor works that i mentioned early you car would feel like a million bucks I hope u used NGK and not Bosch spark plugs

[sanioll]

what is wrong with BOSCH sparg plugs?

i have them and they run fine.

[14.5drift]

nothing. Just preference

[240sxJay]

Hmm I bought Bosch Platnium +4 around 4,000 miles ago..and now they suck I took them out and they were almost collapsed from the tip, i wondered if something was wrong with my engine because my ngk's before never did that. Apparently reading through forums and speaking with mechanics, pretty much anything less than NGK for the 240 will result in poor performance down the line. Since I've bought the Iridium Ngk's and Ngk Spark Plug Wires and now my car is running so smooth, it also feels like it accelerates a lot quicker...(some how my "sticky pedal" situtation was also gone after installing the NGK's) ...You will see in countless forums "You get what you pay for" I paid 2.00 bucks a pop for Bosch Platnium +4's....NGK iridums are 7 bucks a pop, more than 3x the bosch amount.

[ShifDown96240SE]

How about the denso iridium plugs with some magnacore wires, i heard that that s the best setup around with an msd ignition....

[240sxJay]

I agree with you on the Denso's...but those are more elite if you have a turbo or swap in your car, those are for the hardcore racers, i think they are around 15 bucks a pop too! Double NGK iridium's! Now do u get twice the performance? No, but they are slightly better. As for wires i've seen in magazines and forums that Nology is the best ...

http://www.nology.com/hot.html

but they are so f'ing expensive 171.00 for SPARK PLUG WIRES !! O.o, denso and these nology's are a nice hook up , again if your on a swap/ turbo. I dont' believe there would be much difference on a "basic" ka engine.

[ShifDown96240SE]

well, its got a 3 angle, and fully ported and polished, intake, exhaust, 92 cams....its a pretty nice engine, just want to make sure theres a thourough burn on the combustion.

[cory2081]

hows that car run, shiftdown??? I have basically the same mods, except, i havent installed the head and cams yet. gotta port and polish it first. just curious of what kind of gains to expect.

[ShifDown96240SE]

well its not quite running right, sice i put the 92 engine into a 96, i used the 96 intake manifold, but i think that the cam timing is off or something else....but it feels like the engine has some power, but i cant use it yet, im going to turbo this engine, hopefully soon....

[cory2081]

wierd, seems like alot of people on here are having some issues with tuning for some odd reason. Check the cam timing, all you need to do is pull the valve cover