carzy idle ?

We may earn a small commission from affiliate links and paid advertisements. Terms

K

kricket3000

New Member
just got my 88 hf with b18a1 swap in and started the engine and without pressing the gas it rev's up to 5k, is it a vaccum thing or a sensor also no codes so far, also the radiator is not hooked up yet.
 
Last edited:
kricket3000 said:
just got my 88 hf with b18a1 swap in and started the engine and without pressing the gas it rev's up to 5k, is it a vaccum thing or a sensor also no codes so far, also the radiator is not hooked up yet.
Click to expand...

First hook up the radiator and get your coolant level up, could be the coolant sensor.

Most likely its a vaccum leak, was your b18a1 from an auto or manual. Think about it, the engine is getting too much air from somewhere.
 
Check your intake and TB gaskets. From what you are saying I would guess you have a major vacuum leak. If you have some throttle/carb cleaner or some other flammable aerosol spray available you could try misting it along all the gaskets and vacuum lines on the intake and see if the motor reacts. If it suddenly starts running differently when you spray a certain spot than voila you found the vacuum leak.
 
What about the TPS wires? Don't they have to be switched? Or is that only for the DPFI models?
 
cable is real loose, in my reseach i never heard anything about tps wires? as far as spraying something i don't have enough time cause it almost redlines!
 
at any point did you have the intake manifold off the the motor? what about the tb? if you have had any parts removed and re installed I would suggest double checking the gasket at said part. I know when I did my first ever motor job on a civic I pulled the intake and exhaust manifolds off the used a lift adapter on the manifold studs to set the motor in place. The problem was when I pulled the adapter off ant put the manifolds back on I missed a washer on one of the intake studs. One small slip turned into a major vacuum leak and my engine tried to idle about 4500 rpm.
 
Yes, the tps wires to have to be switched when you do a b18 swap, but that should have been done during the swap. The way to tell if that has been done is when you start it, press the gas pedal. If the wires have not been switched, the revs will drop down instead of rise. If it revvs higher, then you know the wiring is right.

I had a similar problem when I did my b18a1 swap and it was the vacuum lines. I did research online (didnt find a whole lot of useful info), and went to the local auto shop (buckys) and asked for a vacuume and ecu diagram for a 91 integra. They just printed it for me, and I ended up just figuring out how to make the car run right based on that diagram and a bit of research.
 
Last edited:
Fernpatch said:
at any point did you have the intake manifold off the the motor? what about the tb? if you have had any parts removed and re installed I would suggest double checking the gasket at said part. I know when I did my first ever motor job on a civic I pulled the intake and exhaust manifolds off the used a lift adapter on the manifold studs to set the motor in place. The problem was when I pulled the adapter off ant put the manifolds back on I missed a washer on one of the intake studs. One small slip turned into a major vacuum leak and my engine tried to idle about 4500 rpm.
Click to expand...
no i have never had anything apart since i got the motor, as for the tps wires i just reused the harness off my old engine and matched up the sensers, how would i switch the wires, this is the frist i've heard of this. i need to get my radiator hooked up before i let it run for long!:D
 
TPS wired wrong wouldn't cause a 5k idle.. you're leaking air somewhere.. Is your throttle body clean, not sticking open a little? There is a stop screw near the linkage that can also stick the throttle open a little, as well as the Idle adjustment screw that could have backed out or completely fallen out.. Have you tried adjusting your idle the proper way?

Look really hard at all of your vacuum lines, make sure everything is hooked up where it should be, no cracks in the lines, no open ports, etc.. You have a big leak somewhere. This isn't some tiny thing..
 
Check your Vacuum diagram routing, I had the exact same problem on my b18a1 CRX and it turned out to be an incorrectly connected vacuum hose.
 
b18vacrouting.jpg


This is what I used to figure out where my lines goto. Its a bit different because this diagram is for a teg and there are a couple differences. If you are running aftermarket intake, leave the dashpot valve unplugged. All it does is make your idol fall slower. It connects to a ported vacuume spot on the factory intake, but isnt necessary.

Also, make sure the map sensor is plugged into the right spot. I didnt have mine hooked up right the first time I started the car and it did all sorts of crazy idoling. I will take some pics of how mine is hooked up when I get home and post them so you can see where everything goes. Also, check the white and orange wires on the ecu side of your harness, and make sure the two identical white wires on the motor side of your harness plug are hooked up correctly. Depending on how you have these, it could cause your timing to be severely advanced or retarded, making it so you cant time it right which might also cause a high idol.
 
I tried taking pics of where my vacuum lines, but it was difficult to see where everything went to, so I just made a diagram for you to use. I hope it helps.

Also, make sure none of your lines are cracked or have holes in them. This will cause you to still have problems.

CivicSwapVacuumeDiagram.jpg


I also drew on one of the pics of under my hood. Sorry the lines and words are hard to read, but if you save and zoom in on it, it helps.

myvacuumelines.jpg
 
phyregod said:
Your motor was an auto at some point!

You should remove all that auto/emissions crap, clean it up a little!
Click to expand...

Huh?? What is there to remove? It might have been an auto some years ago, but I know the last 2 cars it was in was a manual.
 
You must log in or register to reply here.

Similar threads

D
B18C in eg3 electrical/electronical issues
Replies
4
Views
12K
doomEG
D
Blackout_SI
Idle Surge And Overheating
Replies
3
Views
2K
BlackFrog
BlackFrog
G
B15A3 smoking at idle
Replies
4
Views
2K
G_ATL
G
N
B18a1 swap
Replies
15
Views
4K
BrutalB83
BrutalB83
marek94
D16Z6 Intermittent Idle/Power Problems
Replies
5
Views
6K
awptickes
awptickes
Back
Top