Fuel pressure

[GotBoost4Yall]

Ok, looks like my problem is still present.

What is the fuel pressure needed on the CA18DET?

I'm still running the stock SOHC KA fuel pump at 8psi boost, but I've never had this problem before. The car is struggling bad at about 3500-4k rpms. This problem comes up after about a couple hours into the drive. Is there a fuel cut on the ECU?? At 4K rpm it misses,hesitates and dumps a cloud of black smoke, It will go higher in RPM but it gets worse.

Yesterday the Spark plugs were changed, has new 300zx Turbo fuel filter. WTF!!!!!!!!!No boost leaks.

[biosehnsucht]

There is a fuel cut over a certain max MAF reading per different RPM ranges.. but that wouldn't cause it to stumble and then keep going, it would just stop.. black smoke sounds like it went rich..

make sure your coilpacks are ok and the various grounds such as the one on the coilpack harness is attatched, and check plugs

[GotBoost4Yall]

Well I should really think, since black smoke is unburnt fuel I must not be getting a good spark or have a bad connection. I'm not really sure what to go by though,like how big are the carbon tips suppose to be, they all look the same.

[biosehnsucht]

make sure they're gapped right, whatever that is (check FSM), and make sure that the ground strap on the coilpack subharness not only is bolted down but make sure it has a nice solid ground to the chassis from there, it could be bad grounding elsewhere.

bad grounding will make it harder for the spark to fire, since it has to ground through the head, and the head has only that ground strap as a clean ground, there's marginal grounding through the headbolts, and intake and exhaust manifolds bolts, but the head to block, and manifold to head surfaces are all gasketed which doesn't really ground effectively... the only 'clean' ground is going to be that on the coilpack subharness, and like two other small grounding points on the head (forgot where, look in FSM in the EFI harness diagram in the EL section I think its harness 'connector' F11 or so ?)

[Tx-Sx-FS]

about that fuel filter..if im going turbo..would any year or application on 300zx work? im thinking about changing mine but not sure if it has to be NA or Turbo...let me know

[biosehnsucht]

I asked courtesy for a 300ZX filter once, didn't realize they gave me a Z31 - stock KA24E IIRC, or maybe DE - filter until I got home, went back, exchanged it for a Z32, same price lol.

The Z32 barely fits in the bracket I had to brute force it in, I was surprised the bracket didn't just permanently bend out !

[Tx-Sx-FS]

hey biosehnsucht, where u located in DFW? i dont see many 240s in my area but a few...but alot of hondas and tegs...when i turbo and return to texas in a few months (for a weekend) i plan on getting a few races in...what mods you have? also is there a place that says the ca18det injectors or has them in stock and i can order??

[GoofyATX240]

If you mean locally in DFW theres plenty of shops here.

[biosehnsucht]

I'm near 635/plano, in the Lake Highlands area.. my sig has all my info but it only shows on the first post above.. with a pingin' KA I ain't racin' nothing until I swap in the CA, and even then I'm not going to do anything truely dangerous... I'll leave the real speed tests for the tracks..

not to say I wouldn't go bouncing off the speed limiter all day long, provided I've got open road and thin to nonexistant traffic, just I wouldnt race people at speed... (of course one of the first things I'll do when burning a new ECU EPROM is remove the limiter bahaha)

as for injectors, if you don't got any you could grab some DSM 1g turbo low-impedence injectors and get your ECU reprogrammed for em (a few people here can do it for cheap), thats an upgrade.. search this forum about injectors and you'll come across many mentions of them.

[GoofyATX240]

ATS could possibly also reprogram it, but there in Denton.

[Tx-Sx-FS]

yea but im moving to little rock, arkansas next week..so the only place i know of there is Underground..do they tune and stuff there? or is it just manufacuring parts?

[Tx-Sx-FS]

im trying to get some 370cc ca18det ones from this guy whos getting 460s but if he doesnt come through..i was thinking of looking for a shop or net site that sells teh 370s and will have them instock...im getting the 370c and safc for tuning...no ecu..

[iliketocrash]

what octane gas are you using? and what brand gas company you buying from? maybe your o2 sensor is bad? i'm sorry if i sound stupid. but i've found sometimes stupid things i say tend to spark good ideas

[biosehnsucht]

lol iliketocrash this is a ressurected thread from last month, that has been threadjacked

[iliketocrash]

heh. yeah well its hard to keep up with these things when all i do is work and go to my classes. i usually just read one or two posts in long threads like these and then post my reply.but was the problem ever resolved? and what was it?

[biosehnsucht]

I don't recall but he posted a few threads at the time, I don't recall whether it was resolved.. maybe he'll drop in and let us know? lol