Reanimation of 828/1000 - A few problems

[iceman69510]

Just about have 828/1k back to full health, but have come across a couple issues. First the specs:

Rebuilt basically stock engine, I/C, BOV, etc. 3g maf and Evo VIII injectors, Keydiver chip (all taken off my previous 115/2k which was a running vehicle).

Problem 1: The BOV tweets like a bird. I seem to remember this being discussed before, but could only find a compressor surge with a Bullseye turbo thread. Is this a leak somewhere?

Problem 2: After initially starting and running great, the car developed a weird problem this weekend. It now is hard to start and I have to depress the throttle. Chugs like crazy to get going, but will run on its own (roughly) after a few minutes. Continues to run rough now, but initially (Sunday) it would smooth out. Tried a different ECU (just had the other one repaired), no change. Seems like injector 1 was being lazy (slower ticking) and there seemed also to be no change to the running characteristics when I pulled the plug off injector 1, so I swapped a different one in. No change. Coil is fine. I have to pull spark plug one and look at it yet.

I don't know much about injector drivers or the resistor circuit, and will begin studying that tonight in the service manual. Seems like a possibility that circuit is dead. Can I check that with a test light and see pulses?

Thanks in advance.

 

[toybreaker]

I've gotten my ass kicked a few times by single injector problems. /ubbthreads/images/graemlins/hahao.gif

A visual inspection may show a harness/plug/wiring issue.

Looking at the pins of the injector will show if there's corrosion there. If water gets down in the injector connector housing, many times it'll corrode up the pins enought to keep an injector from firing.


You can check for power into the injector at the harness with a quality voltmeter. It won't necissarily read 12v,as it's passing thru the injector resistor, but all four should read the same.

You can check for injector pulse with a quality multimeter using the frequency/dwell setting
be sure to read the instructions that came with your meter to avoid damaging the injector drivers in the ecu!(for the same reason I would strongly recommend against using a testlight to try and check the injector pulse.)

...Without the cool guy meter, one of the best ways is to verify the whole shooting match at once with a "noid" light. They are available at most chain stores, and I think Harbour Break has them on the cheap as well.

It's just a fancy led that plugs into the harness where the injector goes. It will flash when the engine is cranked, and will tell the whole tale about there being power to the injector, the ecu seeing the cas position, the integrity of the harness, and finally the health of the injector driver i n the ecu. ...

If you do have a dead power feed to one injector, start working back upstream.

Check the four coils of the injector resistor with an ohmeter. They should all be the same, ( +/- just a schosche.)

Check the wires at the resistor

Slide the little cotton sleeve back enough to check the integrity of the wires at the resistor. I've seen a few that had the wires breaking/broken there.

This one kicked my ass!

Notice the pin that's slid down a scosche. When you'd plug it in that lil bastid would back out of the housing like a two dollar whore on dollar night ...

So, yea, learned the harday that the pins can back out of the injector resistor connector, and give just enough continuity to fool the voltmeter and the noid light. It was only when the injector was plugged back in that there wasn;t enough continuity to get the job done reliably.

If there's power in and no pulse, it's time to head towards the ecu.

Unplug the injector and ohm out the harness all the way to the other end of that wire at the ecu.

If that checks good, pull the lid off the ecu and check the driver (you should be good there /ubbthreads/images/graemlins/smile.gif , that's for the searchers /ubbthreads/images/graemlins/wink.gif )

If you're stuck in the hinterlands with a RauschSpec /ubbthreads/images/graemlins/killbill.gif fisher price toolkit ... all is not lost ... /ubbthreads/images/graemlins/grin.gif

"Sound" ends up being one of the best ways to troubleshoot this problem.

An injector with internal issues often has a different "tone" to it if you listen to it. A piece of fuel or vacum line held open end down on the injector and the other end held up to your ear will allow you to listen to it and compare it to the others.

Any that sound "hollow" or soft are suspect.

A good solid "click" is what you want to hear.

Sometimes, goo can form on the pintle of a seeping injector on a car that has been sitting for extended periods. That will affect how it opens meters and closes, and bery often can give some weird intermittent prblems. Running some injection cleaner thru the system is almost always a good bet when bringing a vehicle back to the road after an extended slumber. (just do it before you change your fuel filter and plugs and engine oil!)

One of the best ways I found to work this problem was to narrow it down to the individual injector.

A spare cas can be plugged in to facilitate the proccess. Just unplug the one on the motor, (leave it in place) and plug in a spare. Now, you can fake the ecu into firing the injectors without the noise of the engine running. Just turn on the key, and give 'er a twist.

You should hear all the injectors fire.

Unplug any you hear working, as they're just washing down the bores.

Focus on the one that's giving you troubles, and you'll know you got it right when you;ve got it sounding like the others.

Good luck, and be sure to let us know what the problem was!

 

[RedTwo]

You haven't changed the BOV and it's now 'fluttering'? There's greater pressure keeping the BOV piston shut (BOV spring plus post throttle plate pressure feed) than pushing it open (turbo output in I/C pipes at BOV). Is it fluttering at all boost pressures or just the very low (say under 5psi)?
A leak in the post throttle body line to the BOV could prevent the BOV receiving enough vacuum to be pulled open, or a leak in the (probably) cold side i/c pipes could prevent the pressure in the i/c pipes pushing the BOV open.

 

[iceman69510]

Thorough as always, Johnny! Thanks.

As to the BOV, I just put the car together, basically stock as mentioned. Flutter (whistles, tweets) only when letting off the throttle after accelerating. Boost levels should be stock, as I hooked everything up that way intially. I will add a manual boost controller when I get the gauge installed.

Thanks.

 

[Struc]

I'm having a very similar problem with 56/1000 right now. My problem is intermittant, and usually comes on while under high load / boost conditions, and then doesn't go away for a while, but eventually does. During this time when it's running bad, my A/F Gauge goes absolutely NUTS back and forth (not like the normal closed loop operation - more like an electrical problem). It appears to be a problem with #4 on my car, the few times I've caught it while idling at home.

I have a similar diagnostic path to take, so I'll be watching this thread closely, and will also post up what I find.

 

[toybreaker]

Curt,

You may be having an internal problem with the injector that only shows up under a high cycle rate.

Next time it's acting up, try gently tapping the offending injector body on the side with the plastic handle of a screwdriver.

If it fritzes/clears up, I would strongly suspect the injector coil is failing and a replacement injector may be in order.

 

[iceman69510]

Still stumped.

Checked out the resistor, connector and wiring to the injectors. All appear/measure ok.

I have 12.34 V at the injector power wires. Question about this: I have 12.25 V at the other injector wire going to the ECU. I am presuming I understand that the ECU drops that voltage providing the injector a ground when it decides to pulse. If I'm wrong on that, please enlighten me.

I tried another set of plug wires, and plugs. No changes.

I did the actuator test on the scan tool, dropping each injector actuator one at a time. Only injector one seems to not change the running characteristics. But when I listen to it, it sounds normal. /ubbthreads/images/graemlins/dunno.gif

 

Hello Iceman! You might consider the O2 sensor. After all that downtime it could be woozy.
Yes. I am still alive! Do you race your Datsun 510 anymore?

 

[iceman69510]

Hey Bob, 510 has been off the track for 4 years due to finances. Glad to hear from you.

Well, I started to look at mechanical issues since I could not find anything wrong in electrics/fuel. found two rockers arms off ( /ubbthreads/images/graemlins/dunno.gif). Never heard anything abnormal. Cylinder two won't build compression, and one of the intake valves looks low, so I started taking the head back off. No idea yet what happened, but gotta love another setback.

 

[iceman69510]

I think I had a lazy lifter that let the rocker arm fall off, impacting the cam and holding the valve down. Cylinder two intake valve is bent. Off to the machine shop I go. /ubbthreads/images/graemlins/bawling.gif

 

[iceman69510]

OK, 828 is back running and driving, as I actually finished it up except for the downpipe on Christmas Eve. still have one issue:

Problem 1: The BOV tweets on decel. It even does this slightly at low boost conditions. I have checked everything over for leaks. Is it just a bad BOV?

Should get plates for it this week. I reviewed the carfax I received for the car when I bought it a few years ago, and basically this car has had no miles put on it (except for my test drives) since 2001. Will be good to have it back on the road.

 

[Terry Posten]

I should have my old crushed BOV if you want it. It was good when I removed it.

Let me know if you want it.

 

[KiNgMaRtY]

I would try swapping out the BPV for another to see if the fixes your issue. Does it flutter? You said you have have OEM BPV, it is being recirculated correct? Also check that the gasket that seals the BPV to the pipe is still good. They usually go bad upon removing the BPV

 

[iceman69510]

Yeah, I will do that. It is set up like stock. I will borrow the one off my other car for the moment.

 

[iceman69510]

Valve is bad. Tested it today (why don't I own a vacuum pump?) and tried my other one. Works properly now. Must have a bad diaphragm.

 

[Terry Posten]

Send address. BOV is on its way.

 

[KiNgMaRtY]

Good to hear your problem was solved.

 

[Struc]

Wow... I totally missed this thread's resolution.

For the archives, I actually had 2 problems.

I did have 1 bad injector. #4 was sticky, especially under boost (high duty cycle). It would eventually un-stick and run normally.

Problem 2 was related to tuning and my chip from keydiver. I'll leave it at that, as the actual story is long, boring, and mostly self induced such that nobody else would have it happen. /ubbthreads/images/graemlins/grin.gif

The two problems together appeared to be one, so it was very hard to troubleshoot.

 

[3rdstrikedsm]

You should send the injectors to which hunter performance to have them rebuilt/cleaned as they do a real good job and only 19 per inj including return shipping.

 

[Struc]

EH... They are EVO 560cc injectors, and I think I only paid $85 shipped for them. I had a spare set that was going to go into the Spyder, so I just grabbed one of those.