Whats causes this condition ?

[MRKING]

I have Ngk tr55 gap @ 32 and fp at 38 (fp was at 45 but i lowered it with intentions of helping my problem) .50# inj and vortec heads . I have tried 2 diff 50# 3-bar map bins on my ostrich and the same situation arises. If i try to start her up now , it either fires up right away, or not at all . If she doesnt start , its just floods the motor . , I can unplug the injector rail harness behind the motor and crank over and there is enough fuel already in there from previous cranking that the motor will fire right up and idle perfect for 5 seconds until the fuel is gone . I then plug the harness back in and crank and same deal , maybe yes maybe no . Smells awfully rich everytime it wont start and I was told it could be a bad iac valve . Eveything is closed already around here and I wanted to fish for more possibilities with you guys . I will say though that when the motor starts up , it sounds like a champ and idles perfect , no stumbling or hesitation when I hit the throttle or coming back to idle . Rpms would vary up or down a little bit 10-15 sec at idle rpm then up bit for the same timeframe and back down for the same .Thats judging by underhood sound only and I didnt get a chance to check my rpm's since I was checking around for leaks and stuff . I am happy my truck is alive again , but one problem down , and sure thing , another problem arises .

Have any of you had a similar situation with your truck and care to share the solution ?

 

[dhorsman2000]

Re: Whats causes this condition ?

Sounds like maybe a bad FPR.... Pull the vacuum line off of the fuel regulator and see if it is wet (either the regulator or the vacuum line) "tap" your finger on both and that should pull out any fuel in either......

Good luck

 

[ghettosled]

Re: Whats causes this condition ?

a bad iac valve will have nothing to do with start up.. check the cranking fuel in your chip calibrations. With the wide band you should easily be able to tell how much the motor is being overfueled, and adjust accordingly.

 

[MRKING]

Re: Whats causes this condition ?

Well I didnt get into the crank fueling table on my chip yet , but I did unplug all my sensors , cleaned them , and charged up my battery . After putting everything back , to my suprise the truck fired right up . As you said mike , I checked my wb and idle at 1000 rpm was 12.6 afr .It doesnt monitor the cranking afr since it says low voltage while she turns over . After about a minute of idling the wb started to creep up one tenth at a time and the rpm's started to climb the same . I checked under the hood and noticed my distibutor was rotating alittle and I figure now is agood time to set my timing . I started my truck up a couple more times after messing with the dist and it idled at 1500 at 13.4 afr and when I turned the dist the other way , 800 rpm was bogging down the motor . I had to come inside now to continue my husband/fatherly duties and will see what I can come up with tommarrow .Now I need to get a timing light .Thanks .

 

[jwaller]

Re: Whats causes this condition ?

improperly set timing makes for a very hard to start engine. also do what mike said and get to messing with your cranking afr tables bc you need them to be right or it isn't goin to work for you.

 

[MRKING]

Re: Whats causes this condition ?

I didnt get much syclone-time today , but I did get a timing light and checked it . I can only keep the motor running at around 8-12* with the tan wire disconnected , but that is about 600 rpm idle speed and wb shows 14.1 afr .

Truck seems to feel/sound right at about 1k rpm and 13.2 afr , but that equates to 24* from the timing mark on my balencer . When i plug the tan wire back in from the 24* , it shoots inches away from the o* mark . I do have a piston stop to check tdc if my balencer is slipping . I could see a few degrees if it was slipping , but 4-5 inches away seemed like it is something else .If my dist was out 180* would that explain what my truck is doing ?

 

[ghettosled]

Re: Whats causes this condition ?

your probably a tooth off on the distributor.. use a piston stop and turn the motor over.. mark the balancer, turn motor over the other way and mark balancer when it hits again.. mark the middle of your two points and this is your true TDC.. Alot easier and more precise with a large degree wheel, but not realistic in the car. Adjust your pointer to tdc, drop in the distributor and make sure the rotor is facing #1 on the cap.

 

[MRKING]

Re: Whats causes this condition ?

Thanks everyone , I got the timing set to 0* with the tan unplugged and got new plugs . Motor ran good on the plugs that were in it , but would die if I stabbed it to 3k and let it go back to idle . Still had a rich start up condition , but not nearly as bad as before . Idle is 800-1k if I remember correctly and wb afr was 12.8-12.9 . After the day was over, I pulled the plugs and they were still black . They were not more black than before I set the timing and pulled the plugs to turn the motor over , so I hope that problem is done with . I searched more about ruining plugs and rich start-ups and see 28*-30* is what alot of guys are running with vortecs and higher boost . I set mine at 28* and will see how she runs . Thank you.

 

[MRKING]

Re: Whats causes this condition ?

Update with the 28* gap ...
Truck feels way more responsive when running , but every 5 seconds it goes rumble + pop out the exhaust tip . I bumped my fp up to 45 to see if it would make a diff , since my wb was showing a lean spike during each pop ,but it didnt . I am going to lower my fp back to what it was , and open up the plug gap to 29* and see how that is .

So basically , 31* wasnt starting the truck up all the time on the first try . And 28* starts her right up , but has small backfire . I almost feel like I am stabbing in the dark trying to hit something .

 

[MRKING]

Re: Whats causes this condition ?

Tuck really seems to like the gap @ 29.5* and I meant to put the fp @ 44psi but after double checking , it was 48 psi . I ran datamaster and logged a little while in park , stabbing and holding the throttle down for a second . I got a max knock of 4* at around 4500 rpm , and I couldnt get the truck to stall like it would before from rpm going back to idle .I couldnt attach the .uni log file for some reason . Oh well .


I need to patch my current bin with the LM-1 wb patch to get the values in datamaster . Anyone familiar with that process ?