What is it now?!!!!

[TYRODD]

Okay for those of you who dont have an Idea about what my truck is doing, it basically was all about the injectors-search for injectors and the first few threads will be mine :x .

I just got through putting the last three injectors in my Ty, hoping that it would fix my problem for good, but after 3 injectors @ $85 apiece, Im still in the same hole. It strange though, it felt like the same problem I've been having.

What may be a little different about this problem from the times B4, is that my truck starts up fine, Idles fine, zero flutter, basically perfect. But after about a minute, things hit the fan. I get really choppy idle, misses real good at ~1000-1500RPM. When my truck was missing B4 'cause of the injectors being poopy, it was having the same "miss" at the same RPM. But now it really just misses all the time, at all RPMs.
When I went out to test it out tonight, I got to about 65MPH, and didnt like it. It wasnt Knocking or anything like that, I just didnt want to make ANYTHING happen (some like to do this :wink: ).

Anyways,...My timing is fine, FP is fine, no codes, and AFAIK everthing else to my knowledge ::blahblah:: . I havent checked my wires beyond checking if they arc on anything, the engine compartment is about 80 zillion degrees right now, so I wont be doing anything tonight .

Would the o2 sensor be doing this?, can it warm up enough in only 1.5 minutes to cause things to go awry?!! Can anyone give me some ideas? Ask me some questions!!!!

Time for more :drinking: , my car has hurt my feelings once again!!!! :evil:

TIA
-RJ

 

[tyfoo]

i put water in the intercoler after i had it off
just to go mile to get antafreeze and started to break up like you discribe
check the coolent for the points

 

[TYRODD]

Well, I know my intercooler leaks a little, I just tried some cadillac pills last week and they've helped to seal it up a little. There was very little coolant in the TB (thats where it seems to "pool").

 

[TYRODD]

Well, after checking the plugs and wires this weekend, I think I can count them out. They are new delco typhoon specific wires, and they are all between 5.25 and 7.1 ohms-prolly just fine. One thing I did notice is that the PCV valves are NOT the correct parts, they would be used on a NA vehicle, not a FI. The correct GM PCVs will be in tomorrow.

The wrong PCVs wouldnt cause my problems though right? I mean, the stuttering and all....and my intake wasnt dirty at all when I swapped the injectors.

Thanks
-RJ

 

[tyfoo]

basic the same promblem i'm having
start it up smooth idle as it comes down to the 725-750 area it starts to dies, poping out of exhaust and irotic idle almost like a miss
does this sound formiliar?

 

[SeattleSy#1255]

how were all the gaskets when you pulled the upper intake off and TB from the intake? Did you reuse them? Just a thought.

 

[TYRODD]

I still think you're having a fuel delivery/lean problem because of the knock youve been having, I dont have any, but then again I havent really drove it in over a week-trying to take it easy on it. (Ive been pimpen the Impy SS )

My engine will rev up when started to ~1000, then after a few moments it will ease down to 500RPM-totally normal, it idles absolutely PERFECT and there is no miss when reving. After about two or so minutes it will begin to get a little choppy-the needle will "notch" back and forth. Usualy when this starts, if I rev it a little, it will miss at 1k and 1.5k-the same thing happened when injectors where dirty, but all my injectors are fine now. Also, sometimes it may never even have any problems, like it dissapears until I start it again :-? .
It almost feels like a vac leak in that if I rev it in small, even intervals the RPM "swings" down too far and the engine may even die on me. That why I was thinking about the PCV valves being the wrong ones, since they may effect my vaccum.

 

[protosy]

have you checked your o2 sensor with datamaster to make sure its not dead. it sounds like it could be falling into closed loop (use o2 sensor) and then quiting on you because of a dead o2 sensor. you can rule that out real quick with datamaster.

chad

 

[TYRODD]

Well, actually I dont have datamaster at the moment. I have a pretty strong feeling about the O2, because like you said, its going into open loop after it warm up (like after 2 minutes :-? ). For the time being, would a digi-multimeter be accurate enough to test the sensor?, I mean its only going to be between 0-1000mvs :-? My meter def. has that range but....

 

[TYRODD]

how were all the gaskets when you pulled the upper intake off and TB from the intake? Did you reuse them? Just a thought.

Brand new ones from the stealership, In fact, I could/should have just reused the old ones, as I still have them, and they are fine :banghead: .

 

[protosy]

i have never followed this procedure, but it might work.

http://www.gomog.com/allmorgan/o2.htm

basically (what i got out of it anyways).... warm truck up with o2 connected, shut it off, connect digital volt meter to the sensor signal (not power or ground), turn the key on and see what it does on the meter.

maybe that will help.

 

[TYRODD]

Well, I just tried that trick out, my mvs were from about 18mv all the way to about 1400mv, and they switched back and forth quickly-should mean my sensor is okay, besides the 1.4V reading, that seems a little high :-?

What about a FPR?....Ill check my base setting, and see if my guage needle rises smoothly with throttle pressure.

 

[TYRODD]

Geeze,....It feels like Ive checked this a million times now .

Okay FP with rail primed/key off is 43#
FP with engine on, vac. line hooked up is 38#
FP with " ", vac. line disconnected 46#
This is with the stock FPR, that base FPR sounds a little high :-?
Also when reving/checking FP, the hiccuping starts at about 44# and 1000RPM.

Really, the idle isnt too bad since I check the wire resistance yesterday, not as perfect as it usualy is, but not bad.

 

[SeattleSy#1255]

what about a crappy AFPR or fuel pump?

 

[TYRODD]

Well, the FPR is stock-unadjustable, and the fuel pump is 10 months old (wow, Ive almost had the Ty for a year!) its a delco pump. Fuel filter is about 3 months old. Would you think my incorrect PCV valves might have something to do with all this,....well I guess Ill find out tomorrow.

 

[turbodog]

Your symptoms DO sound like O2 sensor. Just because output voltage jumps back and forth doesn't mean it's doing it at the right A/F ratio. What is your idle BLM value? If you disconnect the O2 and run it (yes, you'll get a code) does the idle stay smooth?

 

[TYRODD]

Okay, replaced the PCV valves with the right ones. Then I tried disconnecting the O2 sensor, I disconnected it on a cold engine, started it up and let it run for a while-the Idle was definitly smoother with the sensor removed. I even tried reving it a little, there was no stutter if I rolled into the throttle, If I blipped it, It would stutter a little right when I hit it (A/F not being correct).

I then tried everything again with the O2 connected, it had some pretty violent idle compared to the above.

Note: Through all of this testing, I never through a code. Engine temp was at normal operating temp. and I was giving it a little gas :-?

It wouldnt surprise me if the O2 is a little screwed, My IC leaks and I dont think sensors like dexcool, and after all the injectors and cleaning everything over and over, it prolly didnt help the sensor.

My O2 removal socket will be in tomorrow from NAPA, so Ill get a good look at it.

Whaddyall think of this?

 

[TYRODD]

Any ideas to why I never threw a code?

 

[turbodog]

Definitely should have, with the O2 disconnected. I dunno. Sounds like you're on the right track.

 

[TYRODD]

Well, a new o2 didnt fix anything at all, same problems. I drove it for a while tonight, It felt pretty good until about a 1/2 mile from the house. I was stopped at a stop sign, and the Idle went to hell, like its in open loop. I continued to drive it awhile, noticed that with constant 1/4 throttle pressure, it would miss evenly and would "hit" every so often like it would surge foreward, seems like ignition. The only code I threw all night was a code 32=EGR, prolly cause I dont got one .

Running out of Ideas,.....crap :x