Lean on decel

[1995240sxSE]

My afr on decel jumped up to like 17 or 18. I was in gear reving down from 6500 as soon as I let off the gas. Is this normal? If not how do I fix. I am wondering if this caused me to kill my last motor, and my new one should be running tomarrow and dont wanna kill it 2! I searched and couldnt find a thing!

Detonation can spin a bearing correct??!!?!?! Especially if just one bearing spins?

[NateDogg]

normal

[turbo2nr]

+1

mines doesnt even give a reading on the wideband its reads up to 18:1, i guess its leaner then that..

[WDRacing]

Detonation doesn't spin bearings either. Bearing problems are almost always lube related.

[wild_maxx]

In FI cars the ECU cuts off fuel (not all fuel) to the injectors when the accel. pedel is off to reduce the amount of fuel used and for emmisions purposes.

[Chezedik]

My AFRs in decel have shot to 32:1, doesn't worry me. It is normal. It saves fuel and cuts gases. But I guess my contribution is the same as everyone elses.

I am a post whore.

[1995240sxSE]

Ok cool! never be too safe right!!!

About the thing detenation not causing spun berings I believe that u are wrong! If a cylinder detonated it an cause the rod to be forced in adifferent motion, or put undo strain on the piston/rod/bearing/crank and the weakest link would fail. Usually the cast piston, but if there was high miles on bearings and they had normal wear and tear it could damage bearing. But this isnt what happend to me. I just ran low on oil!!! And over reved A TAD!

[Edub1]

Fuel is supposed to cut back when you let off throttle. Plus, there is no possible way to detonate because VE is way too low. You can run 16:1 or more under light load.

[Chezedik]

I would guess that detonation would cause flat spots or dents on the bearings, not necessarily spin them. I think that spinning a bearing has to be because of no oil.

[WDRacing]

Ok cool! never be too safe right!!!

About the thing detenation not causing spun berings I believe that u are wrong! If a cylinder detonated it an cause the rod to be forced in adifferent motion, or put undo strain on the piston/rod/bearing/crank and the weakest link would fail. Usually the cast piston, but if there was high miles on bearings and they had normal wear and tear it could damage bearing. But this isnt what happend to me. I just ran low on oil!!! And over reved A TAD!

Ok...if you wanna look at it that way, bad gas can cause your rear end gears to fail. Because the car will stutter and if everything is worn, the stutter will shock the diff and shear the pinion gear...

Detonation CAN cause your bearings to go bad, but it isn't because of the knock alone that the bearings went bad. So the answer I gave isn't wrong. Detonation forces the piston down through flame fronts that occur before the piston reaches TDC. So chances are, the ring lands or rods will break before the bearings do.

If your motor is put together like crap, then the outcome is crap. Garbage in garbage out...

WD

[1995240sxSE]

I agree! Just stating that it COULD happen!

[Edub1]

I agree! Just stating that it COULD happen!

Anything is possible but WD is right - in fact the sound you hear durring knock is the sound of the piston resonating from side to side as pressure passes it.

But what difference does it make now.

[1995240sxSE]

future reference general knolladge for all searchers

Good point. I spun #4 bearing cause I was pouring oil and water out and went for a ride any way. I knew the motor was destined to be a door stop! I just wish I could figure out why the new one aint getting fuel!!!

[Chezedik]

How is it not getting fuel? The injectors aren't pulsing? Is the computer coming on?

[1995240sxSE]

I am pretty sure I am getting fuel now, I can smell it in exhaust pipes it just wont fire up! I am thinking dizzy might be 180 out!

[Chezedik]

Switch it, and find out. That would def cause a fuel smell.

[1995240sxSE]

ok dizzy was good, but My injectors are NOT spraying!!! I went around town looking for a noid tester and there is none!!!!!! I am gonna pull a fuel line offf and see if there is any fuel pressure popping up! If I have fuel pressure what else could it be?

[Chezedik]

Check the ECCS relay.

[Florida240sx]

Wait injectors aren't firing but you smell fuel in the exhaust??? Are the sparkplugs wet? Do you have gas in your car???

[1995240sxSE]

I have gas in the gas tank when I pulled fuel rail I didnt see any fuel spray when I cranked it, I am getting spark and the dizzy is set correctly, tested compression yesterday and 188, 188, 185, 188. I cant figure out what is casuing the injectors to not spray! I mean it has to be them. Where is the eccs relay? II checked everything in the both fuse boxes! When cranking motor, on my safc II, the rpm's used to say 250-300 and now when cranking there is 000. It doesnt move. could this mean the distributor could be messed up, as in the cas in the dizzy? I was also thinking that it could be the ecu, I am trying to find one around here to take that out of the equation!!!

I also did diagnostic on ecu and still getting auto transmission codes, (i did 5 speed swap a while ago) But got no codes saying ecu was jacked or injectors were messed up!
Modified by 1995240sxSE at 10:49 AM 5/9/2007

[Chezedik]

1) Pulling injectors to check for spray tells you virtually nothing, and can be incredibly dangerous. Don't do it. 2)The ECCS relay is triggered by the key, and will allow B+ to go to the injectors. The computer will switch the ground sides. So, if you do a voltage check on the common colored wire on the injector harness (probably red) to ground. If the KOEO and you get 12v, then the relay is good, as well as everything before it. Check the ECU.

3) If you are not getting any RPM during cranking you need to run a code check, you will likely see 11 and 21, or at least 21. Check for 11 first, if both come up. This is the Dizzy check, and it is outlined in the FSM. If you have a dizzy malfunction you may have randomly timed spark, but will likely lose injection or will have it randomly timed as well.

To check the dizzy inner-wheel circuit put the key in KOEO and pull the dizzy, leaving it hooked up. Do the injectors click when you turn the gear. If not, you probably have a bad dizzy or broken wire to the ECU.

You know what, this is all outlined in the FSM, you should look at that and use a multimeter to do these tests.

[1995240sxSE]

reading the EC section of fsm is painful for me. I appreciate your help and giving me many more things to troubleshoot! Thanks alot.

[Chezedik]

It can be, some people have real probs with electronics. They don't bother me so much. Check those things, and if need be, I can walk you through the dizzy tests. Check codes first though.

[1995240sxSE]

I am getting code 21 but Have had that one. I have msd6btm with no tachadapter throwing that code! But I rewired it properly, it was backwards on 2 plug that goes into dizzy. Maybe my car is not storring codes cause I cant get it to run!

[Afliction523]

I had this problem. I know it sounds stupid, but have you made sure you did not mix up your fuel lines. I had mine crossed and was sending fuel to the pressure regulator. Make sure your return line is off the bottom of the regulator, and the sending line is to the fuel rail. ....just a thought

[1995240sxSE]

ok pulled the dizzy with the key on and turned it. when I turned it kinda slow nothing. When I turned it fast I heard clicking from the fuelinjectors.

So you dont send fuel to the regulator it goes to the front of the fuel rail???

[1995240sxSE]

ok so the fuel lines were backwards! I am an idiot. I talod someone how mine were I guess kinda confusing! Now my dizzy is off a tooth and My starter when I let off the key it kept spinning just not engaged! All that stuff should be easy tho. I heard the motor sputter tho!!!!!! I think I might be able to get this pig going here shortly!!!

[Afliction523]

ha... I knew I would not be the only one who has done it. The lines are easily crossed if you are not paying attention where they are going. Good Luck with the car man.

[wild_maxx]

ok so the fuel lines were backwards! I am an idiot. I talod someone how mine were I guess kinda confusing! Now my dizzy is off a tooth and My starter when I let off the key it kept spinning just not engaged! All that stuff should be easy tho. I heard the motor sputter tho!!!!!! I think I might be able to get this pig going here shortly!!!

So I was right... good luck on the next problem.

[Chezedik]

I've done that. Keep knocking away at it and you will have a running 240 that you can't drive because it smokes too much!