Hey all, thought id share what ive done over the last few day, out of pure boredom waiting on other parts, i decided to clean up my intake manifold and throttle body.
Basically, cut out some of the webbing on the manifold itself right near where the throttle body kinda is, cut the coolant lines off the throttle body, and made a little steel plate to cover up where the fitv was.
I know it still looks alittle ghetto but its alot neater than it used to be, and of course i had to paint it too…and then the fuel rail… lol
Pulled the tb apart and polished it up as best i could, same with the butterfly, and i dont know if you can tell, but i tapered the intake side, i think its what ppl call the “spoon treatment”, i was quite impressed with myself anyway.
Its still a 58mm tb, i didnt do it for any performance gain and i dont expect one, i was just gonna clean it, but i get carried away sometimes!
Let me know what you think tho
Ive spent the last few months reading through nearly every thread on here, and ive learned heaps, time to give a little back!
The TB and manifold look really great. I wish I had more time to spend on my engine…
(I guess I am stuck looking at car porn for now, LOL)
I’m wondering if you found any white aluminum oxide on the manifold b/f you started working on it?
I noticed that most of the larger aluminum parts under my hood are starting to develop little white spots of aluminum oxide. I thought it was dust at first, because I cleaned the whole engine two years ago when I first started working on the car (it had been parked for about 5~6 years before that), but at least in my case, it was corrosion coming back after just two years.
Cant say there was too much aluminium oxide and either the intake manifold, or the head (cuz thats come off since too!)… altho there were afew spots that looked like it might have started to show, like slight discoloration…
…altho i have to thank the previous owner of the car for that… everything in the engine bay is protected by its own layer of engine oil, did i say layer?, i meant coating! As if he used the oil filler as more of a “guide” than a hole for years upon years!
Took 2 weeks to clean the LH side of the engine bay, now im working on all the power steering and aircon hoses, dont ask me how its so filthy on that side too!
[QUOTE=Denied;2321134]…now im working on all the power steering and aircon hoses, dont ask me how its so filthy on that side too![/QUOTE]Possibly spilled power steering fluid, you can check under the steering fluid reservoir, just slide it up an inch or so, and check underneath using a bent wire, or look with a flashlight. Its a pocket where oil, dirt and spilled coolant can sit and collect for years.
If you see a kine of dirt on the underside of the hood and above the belts, it usually means that oil got on the belts in the past.
I blocked off my FITV when I did my b20 swap, the FITV was messed up, doing the bouncing idle problem. When I start my car in the morning, it will start, the idle will drop to where it normally is when the car is warm and will run rough, so what I do is just manually raise the revs for a little bit until the IACV takes over. Once the IACV takes over the idle stays a little high until fully warm, then the revs drop to normal.
[QUOTE=ProMcCown;2321814]…what I do is just manually raise the revs for a little bit until the IACV takes over. Once the IACV takes over the idle stays a little high until fully warm, then the revs drop to normal.[/QUOTE]Basically you are using the throttle to replace what the fast idle thermo valve does - you supply some extra air at cold idle until the engine warms up. In a warm climate, or if you only drive the car in summer, that works just fine.
In really cold weather, that becomes annoying quickly, because the engine takes some time to warm up. If you start to drive with a cold engine and in cold weather, the car will tend to stall when you take your foot off the gas and step on the brake. (some people do get away with it b/c they have a vacuum leak somewhere)
Some older cars had a manual choke button or lever on the dash, for example '60s Jaguars etc.
Yeah that’s exactly it, I live in central California so the climate is not at as cold as up north. I’ll start to drive once the IACV starts to take in air, on my car it will start to work after the car has slightly warmed up. So when I start to the drive the idle is a little high still so it won’t stall, then once it reaches normal operating temperature the idle goes down to normal. So I only sit there and use the throttle for about a minute or two.
[QUOTE=ProMcCown;2321818]…So I only sit there and use the throttle for about a minute or two.[/QUOTE]One of many reasons why cars have an easy life in California…
For anyone else, here is a link to a PDF document with a generic explanation of how the FITV works, with pics of the inside parts:
I actually expected to have to mess with the idle on the tb, but nope. Started and idled fine first go, instead of roaming ~1000 rpm till it warms up its now almost rock steady at ~800 rpm, never stalled on me. I still wait for the temp gauge needle to start moving before i drive off tho.
That could be because my FITV was maybe stuffed anyway, or it could be cuz of the climate here… if the car ever saw snow or really cold temps i probably wouldnt have removed it, i did it for purelly cosmetic reasons.
I just bought myself a p75 head, intake manifold, and throttle body off a b18b and there is no fitv on there at all, not even a tb mounted one like i was expecting, so i dunno?!
In our cars idle control is split among different devices, some connected to the ECM, some not. If the ECM has the right software, idle air control can be accomplished by a single device.
At some point, Honda and other cars integrated more functions into the ECM, and a separate thermo valve became unnecessary (I think it may roughly correspond to OBD2, but I am not sure that is an absolute rule). Good chance that your new head and intake came off a car with completely electronic air idle control, so it had no FITV. From the pdf document I posted above:
the ecm uses coolant and intake air temp as inputs to determine the output for fast idle, controlled through the iacv. obd2 for sure, and some obd1 models. like all emissions control devices, the manufacturer felt that switching to completely electronic would make it possibe for the ecm to determine a fault in the system, and throw an MIL. and obd2 is ALL about emissions.
one issue i see with deleting the fast idle device is the possibility for a catalyst failure.
unless you have a wideband monitoring o2 in the exhaust stream, you won’t know that you’re running rich. (speaking for the ones in climates whose cars will run without manually holding the idle high).
if you’re running a test pipe, no biggie. but for those of you who aren’t, just know that you are messing with an emissions control device and there will be an effect to disrupting this harmonious system
sorry. i shouldn’t say “no biggie”. of course, running rich will have other undesired effects on the engine and its longevity, aside from just damaging the catalyst
