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QuickMustang
08-28-2008, 04:18 PM
I just rebuilt my engine and added some performance parts and I'm having trouble getting it to start up right. I installed a bigger throttle body, C&L MAF, BHJ balancer, ported 3 angle heads, a bigger cam, Permatorgue MLS headgaskets and ported late model exhaust manifolds. I torqued everything down to specifications given to me by Dave Dalke. When I try to start it, it mostly just cranks over. I would get the occasional sputter. If I put the pedal all the way to the floor then slowly bring it back to idle it will sometimes start up. When it starts I have no tach and it won't idle without me giving it a little gas. It will idle smoothly with a little gas but when I let off it stalls. I'm also reading low oil pressure on the gage, but I really don't believe it because it's a new high volume pump that I blueprinted according to how Dave told me to and all the bearing clearances were dead on. I'm guessing either the gage or the sensor is bad. I bought the car with blown head gaskets so I don't know what symptons it showed before the rebuild because I never started it. I have disconnected the cam sensor and nothing changed. I don't get any codes on the KOEO test (other than 111 which means pass). Any suggestions? Thanks...

94MustangSC
08-28-2008, 04:31 PM
I would take care of the low oil pressure before worrying about anything else. It may be the gauge or the sender, but if it isn't, you've got much bigger problems than it not idling. I had low oil pressure after my last build. It's a sign of a bearing in the process of spinning. Happened after the machinist put circlips where they didn't belong.

QuickMustang
08-28-2008, 04:47 PM
Oh yeah, when it runs the vaccum gauge is pretty steady and if I give it gas it builds boost quickly, so I don't think it's a vacuum leak, but who knows...

S_Mazza
08-28-2008, 04:48 PM
No tach is often related to DIS module problems. Do you get an upshift light while cranking? Also, it would be good to check or rule out the oil pressure as a problem. Can you swap the gauge sender for a real pressure gauge and watch that as you crank?

mywhite89
08-28-2008, 05:16 PM
You'll want to make sure you have oil pressure built up before you even try to start it. I used a custom made tool before I ever put the distributor gear in and primed the oil pump. You'll know when it builds pressure because it gets very tough to spin. If you use an old distributor shaft, hook the drill to it and spin it in reverse for the drill you will build pressure. If you don't have pressure build up, you have problems.

I didn't have an extra distributor so heres what I did. It takes a long shaft that is 5-sided to fit into the oil pump. I used a cheap caulk gun from a hardware store. A lot of those you will notice use a pentagonal shaft. Cut it off, clean up the end a little bit so it fits the pump, and put your drill in reverse on it, and just go idle speed with the drill until you build pressure. If you have the old oil pump you can test fit you oil priming tool.

Chris

QuickMustang
08-28-2008, 05:32 PM
Yea, I primed the engine before I put it in the car. I did get alot of resistance when priming. And i got oil to come up out of the pushrods at the rocker arms...

I just rant the code scanner and i got a 212 and 214 which I searched for here and saw it was a cam sensor problem. I threw the cam sensor on there from my other motor and now my tach works. Now it will start if I give it gas and I turned up the idle screw a little and got the car to idle around 950 rpm, but when I give it gas and let off the idle doesn't drop very fast. I'm thinking IAC now...

I also have a check gage light on and my temp gage doesn't seem to be working...

QuickMustang
08-28-2008, 05:56 PM
OK, I just jumped the wire that goes to the oil pressure sensor directly to a ground which should cause the oil pressure gauge to go all the way high, right? The oil pressure sensor is a variable resistor basically from my understanding. Well the gauge didn't move so I either have a broken wire or a bad gage. So I'm more confident now that i don't really have low oil pressure, I just don't know what my oil pressure is...Well let me know what you guys think about the idle issue I'm having now...Thanks...

Melon
08-28-2008, 06:14 PM
If you just ground the wire and not have it connected to the sending unit, it should just sit in the middle of the gauge in the norm zone. Get yourself a real oil psi gauge in there to keep a better eye on it.

-Melon

KMT
08-28-2008, 06:38 PM
>just rebuilt my engine

Paint anything in the process?

You can start confirming grounds, or use this troubleshooting tree (http://www.frontiernet.net/~miketoni/images/tbird/DISnostart/DIS%20No%20Start.htm) for something a bit more comprehensive.

QuickMustang
08-29-2008, 01:24 AM
If you just ground the wire and not have it connected to the sending unit, it should just sit in the middle of the gauge in the norm zone. Get yourself a real oil psi gauge in there to keep a better eye on it.

-Melon

OK, well grounding it, disconnecting, having it connected, etc. does not move the gauge at all so the gauge is obviously not reading right...I picked up a manual gauge tonight so I'll throw that on there tomorrow and see what it reads...But back to the idle problem, any thoughts?

S_Mazza
08-29-2008, 09:31 AM
I just rant the code scanner and i got a 212 and 214 which I searched for here and saw it was a cam sensor problem. I threw the cam sensor on there from my other motor and now my tach works. Now it will start if I give it gas and I turned up the idle screw a little and got the car to idle around 950 rpm, but when I give it gas and let off the idle doesn't drop very fast. I'm thinking IAC now...

I also have a check gage light on and my temp gage doesn't seem to be working...

It sure could be IAC related. However, you might want to check the codes before you buy a part.

Quik95SC
08-29-2008, 12:43 PM
I just rebuilt my engine and added some performance parts and I'm having trouble getting it to start up right. I installed a bigger throttle body, C&L MAF, BHJ balancer, ported 3 angle heads, a bigger cam, Permatorgue MLS headgaskets and ported late model exhaust manifolds.

I didn't see anywhere that you mention getting a tune for it as well. if you install the TB, Cam, and better flowing heads, you will have idle issues until you get it tuned properly. it is probably running similar to mine and it is running pig rich while idling, when I did get it to run good with a little throttle it was ok, but as soon as I let off the gas it would try and die, because it was so rich.
Check a few plugs and see if they are wet, and there you have at least part of your idle problem.

Smitty

QuickMustang
08-29-2008, 01:06 PM
It sure could be IAC related. However, you might want to check the codes before you buy a part.

Since I replaced the cam sensor and cleared the codes there aren't any codes coming up.

QuickMustang
08-29-2008, 01:10 PM
I didn't see anywhere that you mention getting a tune for it as well. if you install the TB, Cam, and better flowing heads, you will have idle issues until you get it tuned properly. it is probably running similar to mine and it is running pig rich while idling, when I did get it to run good with a little throttle it was ok, but as soon as I let off the gas it would try and die, because it was so rich.
Check a few plugs and see if they are wet, and there you have at least part of your idle problem.

Smitty

How do I take it to get a tune if i can't keep it running? Isn't the correct sample tube for the MAF supposed to keep it close enough that the 02 sensors can get the mixture right. The cam wasn't much bigger as it was just a Morana A cam and the heads were just a home port job.

Quik95SC
08-29-2008, 01:20 PM
How do I take it to get a tune if i can't keep it running? Isn't the correct sample tube for the MAF supposed to keep it close enough that the 02 sensors can get the mixture right. The cam wasn't much bigger as it was just a Morana A cam and the heads were just a home port job.

Either find a trailer to borrow and tow it to a good shop, or if it will run and just has idle issues, get it running and drive it to a Dyno shop Carefully no WOT) with an appointment with a tuner you trust and knows at least something about force induction motors and SC's.

You know after looking over this thread again you could have a lean condition with extra air flow from the TB, MAF, slightly ported heads, and a slightly larger Cam but no larger injectors to go with it, just another thought, but you really can't tell til you get a wideband O2 on there and really see what is going on. It is really a lot of educated guessing right now based on others experience with upgrades.

Don't forget the cost of the Chip/Tune and Dyno Time.

Smitty

bigpoppa822
08-29-2008, 01:26 PM
You have worse problems than not having it tuned. My car ran perfectly fine before it was tuned and has all the mods you have minus the heads. Get it running before you waste your money, THEN get it tuned.

QuickMustang
08-29-2008, 02:31 PM
You know after looking over this thread again you could have a lean condition with extra air flow from the TB, MAF, slightly ported heads, and a slightly larger Cam but no larger injectors to go with it, just another thought

Smitty

I do have bigger injectors...I have a set of 42 lb green tops in there now...

I just replaced the IAC and it seems better but still not right...I drove it around the driveway a little, but it kept stalling in gear...

I know I will need a tune at some point, but I really think it should run better than this without a tune. I have a few other mods I would like to do before I spend the money on the tune (ported blower, better IC, 10% pulley, complete exhaust).

fturner
08-29-2008, 03:29 PM
Did you just put the injectors in now after the fact? Is the MAF calibrated to your injectors?

At startup the car does not use the O2 sensors. The fuel that is present is based off of the open loop fuel tables and the startup enrichment fuel tables which are dialed in for 30# injectors. No resizing of the MAF or the calibration of a MAF is going to change that fuel amount, hence the reason why it is highly recommended to get a tune once you get up to the 42# injector level. Otherwise, your flooding the heck out of your motor and could be doing more harm than good.

For now you can get a chip and a base tune for your car that will get you up and running so you can eventually get to a dyno to get the car tuned in with a wideband etc. If you want more information on that either contact Dave Dalke or myself.

Frit

QuickMustang
08-29-2008, 10:09 PM
Yes, the MAF is calibrated to the 42's and yes I just put both the MAF and injectors on after the rebuild. The engine appeared to be stock when before, but I bought it with blown head gaskets and never started the car before the rebuild so it's hard to tell what was wrong before that.

OK, that makes sense...I am probably running rich because some times to start it after it stalls I have to give it full throttle to get it to start. How much would a base tune chip cost me? How long would it take to have it made/shipped to me?

KMT
08-29-2008, 10:20 PM
>I have to give it full throttle to get it to start

AFAIK, foot to the floor during start shuts off the injectors...

But hey, perhaps it is flooded and pooled fuel manages to ignite. Wonder what the plugs look like.

QuickMustang
08-29-2008, 11:03 PM
>I have to give it full throttle to get it to start

AFAIK, foot to the floor during start shuts off the injectors...

But hey, perhaps it is flooded and pooled fuel manages to ignite. Wonder what the plugs look like.

Yea, that's why I said it's running really rich.

KMT
08-29-2008, 11:30 PM
So what are we thinking the difference is between 'running rich' and 'flooded' at this point? :)

Were those 42s' new?

QuickMustang
08-29-2008, 11:47 PM
Yea, I guess flooded is the right term...

They are new to me, but not brand new. I bought them used off of here from MannySC...along with the throttle body and MAF...

QuickMustang
08-30-2008, 08:38 AM
At startup the car does not use the O2 sensors.

Frit


So can I pull one of the 02 sensors and throw my wide band in there at startup without affecting anything just to see how rich I'm really running?

fturner
08-30-2008, 10:17 AM
You'll need to wait about a minute before the EEC fails that O2 sensor. The computer is looking for a "switch" event at startup so it purposely drives the AFR rich. It'll stay that way for a minute or so then it'll go back to where it should be at high 14's or so. This is once your car is at operating temperature.

You'll see it on your wideband when it gives up trying.

Frit

QuickMustang
08-31-2008, 01:02 PM
Wll at the recommendation of Dave D. I'm going to put the stock injectors and throttle body back on to get the engine broken in. Hopefully that will solve my problem. After that, I'll try to get the 42s and the MAF working right...

QuickMustang
08-31-2008, 06:50 PM
OK, well I get the dunce award. I bought the 42 lb injectors and the C&L MAF used off of the for sale section here. I never thought to make sure the sample tube in the MAF was the right tube. Oops...I'm dumb...I had the purple tube in(the tube for 42s and a 76 mm maf, I have a 73 mm MAF). I went out and bought a red tube, installed it and the car runs good now. I have a few codes to investigate still, but for now it runs. Sorry I wasted peoples time for a stupid mistake. I guess I learned my lesson for next time.

fturner
08-31-2008, 08:14 PM
Your still going to need to get a tune for the 42's as those will be pushing the adpative to the max, so you will be running rich and your spark is going to be way off.

Glad you got that sorted otherwise.

Frit

QuickMustang
09-01-2008, 12:02 AM
Yea, I'm actually considering doing some of the tuning myself and having Dave fine tune it for me since he's been so helpful so far. I have a few more things to tackle before I get to that point, but it shouldn't be too long. Thanks again...