Completed Project Brandon's mild 4.0 OHV build

So, as of 5 hours ago Ronin8002, or James' built OHV block became mine; and with the stea.. I mean deal I got and all the extra goodies he threw in, he seemed a little too happy to get rid of this thing :shifty_ey... lol! But WOW this thing is in good shape! As a christmas gift from my parents, I've been given the opportunity to really dig into an engine like I've always wanted to do. I've watched and assisted a couple chevy 350 builds over the past few months but have never done anything by myself.. so here goes nothin!

The Meat (James' Block):
- 1995 block bored .030 over and torque honed
- Keith Black Hypereutectic 1995 Style Pistons (staying around 9:1)
- Total Seal piston rings
- Clevite bearings
- Stock Water pump/timing cover (awesome shape!)
- Stock Fuel Rail
- SOHC Oil pump/pan - to strengthen up the bottom end
-- Possible port/polish on the lower intake, we'll see when I get there

The Goodies:
- Comp Cams 49-422-8 Cam
- Comp Cams 988-12 dual valve springs
- 95tm heads with minor porting/polishing

(on the way, supposedly 11/28/10)
- SI sev2027 and sev2028 valves
- Delta Cam rockers
and pushrods will come later down the road when properly measured

I'm going to keep a diary as things progress on the motor, once I get all the parts in it really should start coming together quickly. I'm down for any type of constructive criticism you have, if you don't like the way I'm doing something PLEASE let me know, as this will be my true first solo go at an engine! JD4242 has really given me a lot of direction when it comes to the 4.0, by reading through his posts in the forums I'm still baffled by the amount of knowledge he has of these things. So, many thanks to you JD!

First order of business, I need help tracking down a full gasket kit, reasonably priced as the budget is dwindling down, I hear an ebay seller has them for around $130??, as well as new head stud/bolts. I'm not feeling ARP's $400 set of head bolts/studs. Does anyone have any suggestions or leads on either?

Thanks for lookin! Here's a couple of teaser pics! Pics of the motor when I get it all unpackaged and on a stand.

-Brandon

 

[Xeek]

yea ive seen it saying its gonna rain every hour all day, still no rain yet

 

[Brandon96]

Ok, update and a few questions for some 4.0 guys.. It might just need a tune, but I've got a slight issue that's really irritating me.

The engine can't hold a steady idle to save its life. It fluctuates between 650-800rpm when warm, or when it enters closed loop. When I start it up cold and let it warm up it does fine, idles right at 650-700rpm and lopes just like a cam is supposed to. It also still hesitates on acceleration and gets TERRIBLE gas mileage (5-6mpg) at certain RPM/Load combos, though I can't notice a definite trend.

It still smells like it's running rich. No vacuum leaks. I cleaned the MAF, IAC, PCV, the FPR and both ECT sensors are new, 02 sensors are new, the cats don't smell too bad and they don't sound clogged but you can definitely tell they're working overtime to compensate for the rich condition. I even tried unplugging the MAF and it won't run any better.

I suspect a bad EGR or DPFE, can anyone verify or deny this idea for me? I plugged the vacuum lines for the DPFE and it still ran crappy. Then unplugged the vacuum line for the EGR and still, no code/change. This is REALLY driving me nuts.

Any ideas will be greatly appreciated!

 

[Dono]

Hey Brandon, I cant be very helpful, but how do the spark plugs look when you pull them out? Lite brown? Im just thinking this might help in knowing if your truely running rich.

Then maybe someone can chime in on what things to look for.

 

[Willard]

I would say EGR is not the problem since you unplugged it with the same results. In all honesty I don't think it will affect idle, provided it isn't dumping EGR at idle. It also shouldn't really matter until the truck warms up since it has to be at operating temp to activate the EGR.

On the other hand, if you have a seriously stuck EGR valve, it could be constantly dumping the EGR no matter what the condition, but I feel like the problems would have no way of being intermittent.

Have you checked out either the crank or cam position sensors? In my experience with a first gen the cam position sensor really didn't make a noticeable difference in driveability, but I know the crank sensor can. And with yours being newer my experiences with that might be a moot point.

 

[Brandon96]

Thanks for the responses fellas,

Dono,
The original set of plugs I put in the motor with the build were COVERED in a carbon-like black film, evenly, on all 6 plugs. That was pre- my 02 sensor issue. Since then I've switched them out.

The new set I have in there now have ~300 miles on them and they are starting to get the same black carbony build up on them. I attribute this to running rich as I can also smell a strong unburnt fuel smell when standing behind the truck.

Willard,
The cam sensors between the 1st and 2nd gens, to the best of my understanding, are different? My 2nd Gen has the cam position sensor on top of the oil pump drive or "Cam Synchronizer Assembly" as Ford calls it. There is only one way the assembly can be inserted (WITH the alignment tool attached) and I have a new sensor on top of it.

Also, I think the cam sensor (atleast on the second gen) only helps the truck upon startup. Seeing how it starts up on the 1st or 2nd turnover every time.. I hope the cam sensor is good

The crank sensor might be worth checking out though, I'm not 100% sure on when it comes into play for and what info it gives that is needed by the PCM. I know I thoroughly cleaned it when I had the engine apart, I'll definitely double check it and look into it. What do you think it could be affecting?



EDIT --

Crankshaft Sensor - Controls spark
Camshaft Sensor - Controls Injectors

Both worth checking out / cleaning i suppose.

Just found out that if the Camshaft Position Sensor goes bad, it doesn't know when to fire the injectors so it just does not fire them at all. Learn somethin new everyday...

 

[Dono]

I wonder if it could be a teperature sensor? It sounds like the motor runs fine when cold. Just thinking out loud.

 

[Brandon96]

This just went from irritating to pissing me off. :fire::fire::fire:
(try to keep an eye on the RPMs while I'm holding still.. they fluctuate +/- 200 constantly)


MAN this is going to be the death of me. It runs fine, in fact a little bit better than normal now. I can feel more power, can feel less load on the engine almost as if it's getting a much better fuel/air mix.

My theory is that there is a sensor sending the PCM a false reading which is telling the ScanGuage I'm getting over 200mpg's at full throttle. Which sensor that is.. I don't know.

Which sensors 'talk' to the PCM that would provide info on the Air/Fuel mix during acceleration and driving conditions, not idle? I'm suspecting one of them justt went bad, and that is the one that has been giving me grief.

Do I make an sense? gahh I'm so mad at this thing today..

 

[Brandon96]

Also, Dono,

both my ECT (to PCM and to dash) sensors are brand new and are within 1-2 degrees of each other at all times, so they are both good I hope.

 

[Ronin8002]

Which sensors 'talk' to the PCM that would provide info on the Air/Fuel mix during acceleration and driving conditions, not idle? I'm suspecting one of them justt went bad, and that is the one that has been giving me grief.

Do I make an sense? gahh I'm so mad at this thing today..

o2 sensors and MAF....maybe TPS also. Not completely sure how the scanguage 2 does the MPG calcs...I have heard it uses sensors and I've also heard it uses an internal calculation based on rpm, engine size, and load as measured from the TPS.

You might what to go under the setup menu and under fuel and cutoff. Make sure your cutoff value isn't lower than what your TPS value is at idle.

 

[Ronin8002]

I also think a trip to the dyno that includes a wideband o2 datalog will help you know for sure how the a/f is and what they can do to help tune that beast.

 

[Brandon96]

o2 sensors and MAF. Not completely sure how the scanguage 2 does the MPG calcs...I have heard it uses sensors and I've also heard it uses an internal calculation based on rpm, engine size, and load as measured from the TPS.

You might what to go under the setup menu and under fuel and cutoff. Make sure your cutoff value isn't lower than what your TPS value is at idle.

Can you further explain this?

It's never ever done this before and has always been fairly accurate so I'm pretty confident nothing changed etc etc.. but worth checking out. The scanguage says my lowest TPS value at idle (though I don't know what this number means) is '17' or '13' I can't remember..

 

[Turdle]

Hmmm,
It would seem the MPG issue might be related to the driveability
Does the MPG display use Maf sensor readings for it's computation?

 

[Brandon96]

Hmmm,
It would seem the MPG issue might be related to the driveability
Does the MPG display use Maf sensor readings for it's computation?

That I do not know.. I was trying to figure that out now/hoping someone on here knew what ScanGuage uses to obtain that info.

I was thiiiinking if I can track down which sensors/calculations ScanGuage uses, maybe I can trace it to a specific sensor which is causing me these headaches. Right now I'm just hoping it's no the PCM.

 

[Turdle]

OOps, sorry, I so your help post on the other place and posted without really reading. I see it was already discussed.

 

[Ronin8002]

Can you further explain this?

It's never ever done this before and has always been fairly accurate so I'm pretty confident nothing changed etc etc.. but worth checking out. The scanguage says my lowest TPS value at idle (though I don't know what this number means) is '17' or '13' I can't remember..

Scanguage has a feature under the setup -> fuel part that is called "cutoff" Basically it's for vehicles that turn their injectors off when at speed and coasting. Our vehicles don't do this, so the value listed under "cutoff" needs to be set about 4 higher than that on what your TPS value is at idle. Otherwise while moving at idle your MPG will show as some ridiculous number. Might be worth a look.

 

[Ronin8002]

Also, did you check the voltage on your TPS? Try this link:

http://www.explorerforum.com/forums/showthread.php?t=79362&highlight=adjust+tps

 

[Ronin8002]

Hmm just watched the video. 9999 MPG at full throttle eh? Weird for sure.

Still suspect TPS and maybe MAF after that.

 

[Brandon96]

No problem Turdle!

....

Okay, just went out to check. My TPS value stays at 18 during idle. Doesn't move, fluctuate or anything, which is good.. I think.

It is my understanding that this means the throttle body is open 18% during "closed" throttle, or idle. Right? Okay. With my TPS value at 18, I went in and checked the fuel cutoff value, it is set at 24.

I personally did not set it there, it was just... there. I suppose from the factory?


EDIT --

No no, 9999MPG immediately when I let off the throttle, then is drops back down to 100 something after it starts to coast. That has ALWAYS been the case though. Even with the old engine and when it was running healthy when I first got it.

 

[Ronin8002]

I am not sure if the number is a percentage...I think it's probably just for reference purposes.

There is a default cutoff value in the factory settings....don't remember if it was 24 but they said in the manual that it isn't crucial and that for most vehicles the default is fine. Just thought it would be good to check.

I think you should look at your TPS voltage as per the other thread I posted.

 

[Brandon96]

Will look at the TPS now, it seems easy enough. I should look for .95-.97v with the throttle closed I'm assuming...