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Takumi
18-01-2004, 02:23 AM
Hey guys,
been on holidays for a while so havent been driving the lude (3rd gen 88 si4ws), and a bit before that, so its only really been getting driven every fortnight or so. Anyway, its developed a rough idle, as if it's missing. I'm thinking leads and distributer rotor or something, ive put in some cheap plugs to see if my old ones were the problem and nothing changed.
Anyone had similar problems? I may just be imagining things, but yeah it shakes the car a bit at idle about every 5 seconds or so, like sometimes it'll idle fine, then sorta shake you around, but the tacho doesnt fluctuate much, if at all.
What do you guys reccommend?

Thanks in advance.

[[d a n n y]]
18-01-2004, 08:58 AM
let the car idle for about 10mins and see what happens...

bennjamin
18-01-2004, 09:39 AM
]]let the car idle for about 10mins and see what happens...

And then it blows up...Danny this problem is constant - not "just when the car is warming up"

Hi Takumi - you could use "trial and error" - change every small thing and see if the problems disappears - There is a few things to watch out for -
Spark plugs , ignition leads , distributor , fuel filter , injectors , - try changing one to a fresh new item , then REST your ECU by unplugging both you battery terminals for about 5 mins , hook up and the engine should run on default settings - hopefully ironing out any hiccups.

I would just take it to a mechanic rather than rely upon us "net doctors" - but I have told you basic things to consider...Good luck !

LUD02C
19-01-2004, 06:43 PM
I have the same thing as you buddy!
The 3rd Gen Prelude's are setup differently to most cars!

When you install a air/fuel ratio you will notice!
In lower revvs it allows much more air then fuel, (more then other cars)

That is why it shakes alot cos it is changing from alot of air to air/fuel ratio's!

if that makes sense to you!
I can't explain it good...Sorry!

But, you have nothing to worry about!

gen2_si_lude
14-02-2004, 11:29 AM
This is a common problem some FI ludes can develop, it may apply to you:



Replacing the Idle Air Control (IAC) Valve

The symptom that normally tells you that you need to replace this valve is when your car, having the 85-87 Prelude Si or the 86-89 Accord Lx-i engine (the FI ones), starts to idle erratically alternating up and down.

The location of the IAC is on the throttle body on the fire wall side.
You are going to want to remove the stock airbox connections in the area for ease of working. The stock airbox is held in with two 10mm bolts. Once removal of the stock airbox is complete, you can disconnect the two hoses. Removing these is not difficult, but maybe a little messy. Next is the removal of I believe 3 bolts, I don't recall what size they are, probably 10 or 12 mm's. Once you have it off, the installation is reverse of the removal.

Maybe suggest this if you take it to the mechanic.