asianguy02

iTrader: (4)

I have a 94 with what appears to be a JDM engine and harness. The motor was rebuilt by me, makes excellent compression, and will start when it wants to. The problem I am experiencing is normally I can sit and crank the engine all day and night, but it will refuse to start by the starter. If I pull it, it will start, but will idle around 3k RPM, obviously not good. It is getting fuel/spark/air, and I notice that when it does start, the throttle is completely unresponsive, will not accelerate, or decelerate. Engine is throwing two codes the numbers are 28 and 39, since the engine is JDM, it has neither of these so I assume that is ok, and not in limp mode. One thing that is kinda off is the TPS since I cant adjust it properly unless the Fast Idle Cam is open, but from what I can tell if it would warm up correctly the thing would be able to be adjusted correctly.

Also it seems like the engine is flooding, because when I pulled the spark plugs the leading were a little wet, but the trailing ones were soaked in gas. I have tried de-flooding it several times but it keeps on happening. I sent the injectors out to be cleaned and flow-tested to witchhunter performance and they came back with good numbers, and all passed.

Tried everything with two different ECUs, and although my wiring harness is in craptacular shape everything comes back as it should from the sensors, and goes out like it should for controls. Coils and plug wires are in good shape. only mod is a downpipe.

Any ideas?

asianguy02

iTrader: (4)

I stand corrected on one thing, would not pull start again just now, engine revved up but wouldnt catch, previously, would catch and idle would shoot to 3k RPM.

Gurew

iTrader: (4)

hrm

rd_turbo

iTrader: (4)

You might have a couple of issues, is your car a JDM or just the engine? What ECU are you using?

Did you have the TPS removed at all? If so, were the tabs correctly engaged when you put it back on? It almost sounds like you may have installed it incorrectly.

When you say compression is good, how good is good? Is it a fresh build?

asianguy02

iTrader: (4)

engine is JDM, I think the EM harness is too, the car itself is USDM, and I have both a JDM and US ECU. Did have to replace the TPS, did this with the TB off and everything was cherry, TPS tabs were making good contact. And yes this is a fresh build compression PSI is about 90-90-90 for both rotors.

asianguy02

iTrader: (4)

bump from the dead, but I am still having problems, and I have been searching around old and new threads, and I heard it mentioned that it is possible to explain a ridiculously high idle with a vacuum leak somewhere. Could this be related to what I am experiencing when I get the car to start, and then explain how it dies? I managed to get the car started today briefly, and it would start, idle around 1k RPM would run worse when I hit the acceleration pedal but otherwise be unresponsive, and eventually it would wind down and die. Like I said before, I just cleaned the injectors, and after testing the fuel pump again it gave me 30 PSI when I jumpered it w/ the diagnostic terminal, but the pump is otherwise still running when it is supposed to, and I can hear it when its working and the engine isnt started. Should I get a boost/vacuum gauge to see what is going on?

RotaryEvolution

iTrader: (30)

you sure it is gas on the plugs? is it spewing smoke when it DOES start? if the compression is good and the injectors have been serviced i would look at the possibility of coolant getting into the engine. what is good compression to you also and how did you do the test? cranking RPMs should be around 400 RPMs ideally. also look at the MAP sensor and vacuum line to the throttle body.

asianguy02

iTrader: (4)

im about 90% sure its gas on the plugs, it smells like gas and lights on fire and burns fast. It can start after its been sitting for a while, its just a little b***h about it, but it will only run for a minute or two before slowly dying off. When it starts, it spews white smoke that *does not* smell like coolant/feel like steam, it just smells like extremely rich exhaust. I checked the compression with a rental kit from kragen, screwed the nipple into an adapter and that into a plug hole sealed the nipple/adapter with teflon tape, that gave me three even bumps at 90 PSI. Cranks around 400-500 RPM, and coolant level has been stable since I was able to get it going long enough to burp the system. Ill check out the map sensor and vacuum line to it tomorrow.

And thanks for the quick reply

RotaryEvolution

iTrader: (30)

well i would check the fuel pressure if the MAP sensor lines all look ok. you can still be running lean and have the car flood out after trying to restart it if it is still breaking in. the fuel pump could be cutting out.

asianguy02

iTrader: (4)

just tested the fuel system pressure when trying to start, i have a solid 40PSI w/o jumping the pump via the diagnostic terminal, it'll drop about 2PSI when partially starting and stabilize there. MAP sensor checks out how it should.

Supernaut

iTrader: (83)

I'm confused, I thought 90psi compression was barely above minimum. Who did the compression test btw?

http://www.rotaryresurrection.com/3r...ion_check.html

Rx72Heaven

iTrader: (2)

Ever thought maybe the crank angle sensors are not working? This could be the issue, the engine not firing the plugs/ injecting gas at the correct time. Give it a check.

asianguy02

iTrader: (4)

Doh my bad, should have bookmarked that site ages ago.... F*********K me.... time to check it again, so im not even more of a dumbass

CAS is good, that was one of the first things i checked when it went wackey.

Rx72Heaven

iTrader: (2)

Ok good to know man. Well good luck in your search of that elusive gremlin!

asianguy02

iTrader: (4)

compression came back 30-30-30 peak at 60 on the rear rotor, 35-35-35 peak at 75 on the front, sourcing rebuilds now.

RotaryEvolution

iTrader: (30)

ouch