xsohaib

Hey guys,
I don't know if ya'll recall that I had ported and polished the head on my ES and then it was overheating (turned out that the head gasket on the rear bank was not installed properly thereby blocking the coolant flow. Anyhow, I was pondering about installing a wet shot NOS kit. My question is that are the kits DIY? What components need to be there for making it a DIY?

I went to a local speed shop and they recommended that after the port and polish one should do a dyno tune, and add an AFC computer. How true is that?

I was specifically looking at some of the NOS kits on ebay going for $500. link is as follows
http://cgi.ebay.com/ebaymotors/ZEX-3...QQcmdZViewItem

Thanks

Sohaib

hkbladelaw

Remind us why you need NOS?

xsohaib

Oh, apologies,
I just don't feel that I have enough power, and no joke but just want to dump some money into modifying my car. I think it just might be that I have around 6-$700 I want to spend on the car.


Thanks
Sohaib

mcelligott

A tune wouldnt hurt, but if you plan on doing a bunch of other mods, just wait until you have them installed.

I have used an NOS brand wet kit, an NX dry kit and a zex dry kit, all worked pretty well but I prefer the NOS brand one.

If you dont plan on upgrading your fuel system, go with a wet kit.

Pheonix

Definately.
I'm not a fan of AFC's. You pay a lot of money, and they do one thing. (That in all honesty you already have control over to an extint.)

For $100 more than an SAFC, you can buy an SMT6 that is advanced enough to run the car by itself. You wouldn't want too... But the feature list is insane for the price.

xsohaib

I (and my mechanic, a performance shop) hooked up the Zex nitrous kit (wet).

I went for a test run on the 55 shot and everyhting seemed really well. Then on the way home even though I did not hit the NOS even a little bit, but the car started to misfire, and the transmisssion hunting for gears as if, and missing really bad, I tried to just get home (about a mile) but at this point the car shut off. The rpm fluctates and the car is running really really rich. My mechanic came in and checked the compression on the front three cylinders and he said they were perfect so assumed that the back three should be good too. When the plugs were taken out they were black and all burned out.

How can I rectify this problem. Is this something that would happen everytime I run NOS. Is there a permament solution.

Thanks

Sohaib

mcelligott

Get some colder spark plugs and dont go back to that mechanic.

xsohaib

Thanks for the reply mcelligott, I changed the plugs myself and the car still runs like cr#p, it is still misfiring and missing and running rich. Any suggestions.

Thanks in advance

Sohaib

mcelligott

Did you retard your timing a few degrees as well?

Pheonix

A good spark plug guide I put together.


My recommended plugs - NGK:
Cars:
Engine: - plug code, part number, pre-set gap
Stock VS 1 heat range colder w' stock gap VS 1 heat range colder w' no preset gap (0.0315"). (Where applicable.)
2vz-fe - BCPR6ES-11 6779 0.044 - BCPR7ES-11 1095 0.044 - BCPR7ES 3330 0.0315
3vz-fe - BCPR6ES-11 6779 0.044 - BCPR7ES-11 1095 0.044 - BCPR7ES 3330 0.0315
1mz-fe - BKR6ES-11 5553 0.044 - BKR7ES-11 2387 0.044
3mz-fe - BKR6ES 3783 0.044 - BKR7ES-11 2387 0.044

Trucks:
3vz-e - BKR5ES 2460 0.032 - BKR6ES-11 5553 0.044
5vz-fe - BKR5EKB-11 3967 0.044 - BKR6ES 5553 0.044 - BKR6ES-11 5553 0.044 - BKR6ES 3783 0.015



You want NGK 1095, or 3330 - the underlined plugs.




Like MCE said, you may want to retard the timing 3-5*.

xsohaib

So, the mechanic called and said that the AFC is messing things up. I thing that the AFC may be hooked up wrong to the ECU or something. Also, the timing was not retarded. He did the tests and said that the engine is not damaged, but that the engine is running really really rich.


Thanks

Sohaib

Pheonix

That's because the mechanic won't admit he doesn't know what he's doing on this engine.


The 3vz-fe AFM is Denso's generation II AFM. It runs a backwards scale to most sensors.
Lower voltage = more fuel
Higher voltage = less fuel
Rrrrrrr I hate those cheap little things. Just take the AFC off (bypass it) for now, or set it to 0% across the board. (AFC's are known not to pass the same voltage through all the time when set to 0%)



If it were me:
1) I'd kill the AFC (for now)
2) retard the base timing by 5*
3) lean the afm cog 5 clicks - until you're running more n2o
4) Change to the NGK plugs I showed (Which would cost about $10usd)

xsohaib

Thanks for the reply pheonix, Allow me to explain the whole story now, I was due to ship out my car to London Last week, since I am headed there for my clinical rotations. Well, after all this crap went down, I had to change my ticket to london as well as the shipping schedule. The guy has been working on my car non stop basically morning to evening for the past 4-5 days. Today, he yanked out the AFC all togther because I told him to do so, changed the plugs about 2 times, (Bosch ones, since I had already bought them). it turned out that the place where the Nos nozzle goes into the intake had a rip in it and hence it was runnig really rich, due to the extra air getting into the engine past the MAF. He fixed the little rip with silicon, and then tried to hook up the NOS again, but since the negative terminal of the battery was off for so long and so many times, hence it needed to be programmed again. He tried to program it but in the begining due to some mix ups I guess, it got set to the point where the NOS would get shot into the engine when you let go of the throttle, instead of depressing on the throttle. Anyways long story short the car started to run like crap again. I told him that maybe there is a lot of fuel dumped into the engine due to the messed up programming, so we shut the car off and I purged out all the NOS, turned off the activation switch, there was still some fuel in the line running from the Solenoid to the intake, so he disconnected that and dumped out the excess fuel, changed the plugs again, disconnected the wire going from the solenoid to the TPS, and I started the car back up, it still ran rich, I mean really rich. So He said that depress the gas pedal and keep at high RPM's so as to burn out the excess fuel that may have been left over. After about 3 minutes of car running really rich, everything became fine the A/F ratio, the idle etc. But after about a minute it started running rich again. The compression checked on all 6 cylinders is consisent and within range (according to the mechanic). I told him to disconnect the negative of the battery and reset the ECU for 15 min and try it again. When done so, again it ran rich for first few minutes, I had to keep my foot on the gas to prevent it from shutting down, and then it ran fine for a little bit and then, it started to misfire again, running really rich.

My main concern at this point is just to bring the car back to its original condition and he is going to yank out the NOS tommorow.

What do you propose I do next. Should I tell him to retard the timing even if I don;t plan on running NOS?

Thanks

Sohaib

xsohaib

Well, the mechanic did not show up, so I think I shall have it towed to the mechanic I used earlier for changing the valve stem seals and the timing belt, water pump, cam seals etc.

Opinions on what to tell this new mechanic?

I was thinking about NGK plugs, check out the O2 sensor, and what do you guys think, should I have the NOS kit taken out for now?

Thanks

Sohaib

Pheonix

Like I said, this guy doesn't no what he's doing. Just to pick that apart.
Good!
Bad. Bosch plugs run notoriously assy after a few thousand miles on Denso ignition systems. You NEED to stick with Denso, or NGK plugs period.
*ESPECIALLY* with any kind of hi-po output. Even more so with n2o, or boost. Bosch (American) spec/made plugs have relatively small heat ranges they work well in also.

Completely incorrect. A vacuum leak causes the engine to run lean (Too little fuel). Not rich (too much fuel.
If you were running rich before - you are running richer now that the vacuum leak is fixed.

Oh that's a completely load of ***. This OBD-I computer doesn't store the ONE fuel trim it has to begin with. It's a live tune in closed-loop only. You can't reprogram them to begin with LoL!

What the hell is he doing? You're running a basic setup right? It's a wide open throttle switch, and probably a safety / "cool go fast" button.

It's a pair of switches wired in seires & a freaking relay. What the hell is so complicated he can't figure that out!?
hahahahahahahaha

Good. He has no use for the TPS... He's probably screwing the VTA signal coming from the TPS to the TCCS - which is causing it to dump a boatload of fuel in.
Trigger switch on the pedal, and a safety switch. There is no use for doing more than that. MORON.

That doesn't mean anything. The specification is a minimum of 142psi, "normal" is 178psi. 150psi & lower is blown up & the average engine with wear & tear is going to have 165-175psi of compression. If he can't tell you numbers, him doing a compression test is USELESS.


The problem isn't compression. Doesn't mean you're not blown up, but this is simply too much fuel, or not combustion the fuel you have.

Pull the EFI fuse out of the fuse box nearest the battery. Count to one hundredth of a second & put it back. The ECU is reset. No need to kill off the radio & clock presets (etc.), nor stand around waiting.

Telling ya. This guy doesn't have a clue.
1) Get all the crap off the TPS, and every other sensor he's tapped into for no reason.
2) Pull the n2o solenoid OFF the car to make sure his stupid wiring doesn't have it spraying all the time.
3) Put a voltmeter on the VS signal coming from the AFM (Search for my AFM cog tuning post on how to cut the top off & check the voltage by touching the arm - instead of having to splice into the wiring).
At idle: 2.7-2.9v
At WOT: 0.3-0.23v

If it's not reading that, then the AFM is out of adjustment - if it is & you're still running rich, the most likely cause is the TPS being out of adjustment.


Past that, make sure there isn't a fuel injector frozen open. It's rare for Denso injectors to stick, but it wouldn't be the first time!



The guy may know cars, but he seems completely clueless on these.