Surging and bucking when warmed up

[short1500]

Would probably be best to use a scanner and then leave it in test mode while you drive around, once you verify fuel pressure. I initially checked my TPS with a sweep and it was fine. But toward the end when I was just about ready to pull my hair out I decided to drive around for the day with the brick sitting next to me. I was at a light when it started to act up and saw the TPS voltage fluctuating a bit along with IAC counts, bingo.

Working trying to get me a scanner. Weird that mine does it a soon as it hit operating temp every time.

 

[BVRPLZR]

Concerning the scan tool:

I bought an ALDL cable/data logger from Moates that I used for a while and it was great. Moates doesn't sell them anymore, but it seems like BoostedNW has stepped in to sell a direct replacement. You'll need a laptop and winALDL or TunerRT (I honestly thought WinALDL was easier to set up and more than adequate for just verifying sensors, although neither are difficult to use)

Having said all of that, if you ever think you might want to alter the tune on this truck I would read up about Flash EBL II as a complete replacement for the stock ECM and not even bother shelling out the cash for a dedicated scan tool or an ALDL cable (as long as you have a laptop)

Not saying that you NEED to spend money on either of these things to make your truck run, but being able to interface with the computer that's controlling your engine will help you rule a lot of stuff out quickly.


Also, does it surge at idle when it warms up or is it just when you hit the gas/are at cruising speed?

 

[short1500]

Concerning the scan tool:

I bought an ALDL cable/data logger from Moates that I used for a while and it was great. Moates doesn't sell them anymore, but it seems like BoostedNW has stepped in to sell a direct replacement. You'll need a laptop and winALDL or TunerRT (I honestly thought WinALDL was easier to set up and more than adequate for just verifying sensors, although neither are difficult to use)

Having said all of that, if you ever think you might want to alter the tune on this truck I would read up about Flash EBL II as a complete replacement for the stock ECM and not even bother shelling out the cash for a dedicated scan tool or an ALDL cable (as long as you have a laptop)

Not saying that you NEED to spend money on either of these things to make your truck run, but being able to interface with the computer that's controlling your engine will help you rule a lot of stuff out quickly.


Also, does it surge at idle when it warms up or is it just when you hit the gas/are at cruising speed?

Does not surge at idle. Only when you hit the gas in park or when driving after it warms up.

 

[short1500]

Ok so I did a fuel pressure test today and found a big issue. I found my new fuel filter was clogged with rust. Picture of pressure is before and after fuel filter. Also picture of filter and crap that came out of it. I changed the filter out and took it for a drive. It ran better and then bam started that bucking crap again and then finally got some codes. I pulled codes 15, 43, 44. All 3 off these sensors are brand new. I'll be ordering a new fuel tank here soon to get rid of my rust issue. What would cause these 3 codes?

 

[Moleman]

Code 15 ecm detects low coolant levels.
I do not know since I didn't think these ecms could detect coolant levels. The only thing I can think of is the grounds on the thermostatstat being dirty one of them. Is the ecm ground.

Code 43 is esc intermittent short to ground in the bypass circuit. Sounds like you got either a short to ground or the computer can't detect the pathway to the distributor. Cuid be a bad pick up coil or icm or the distributor has a lot of play and is worn.
I've delt with oil getting up into the EST distributor before and shorting the icm and pick up coil. But that can't be since your distributor is rusty.

Code 44 is o2 sensor for lean condition . This is probably due to the lines being closed with whatever that crud is.

I do t k ow that much about tbi thats why i went to the darkside.I'm just going off of similar experience when I ran tbi and tbi heads then tbi and vortec heads.

The 2 people that could help you out are playing withtbi and l31 express. Those guys are the ones with the computer PHDs. They know that fuel values,data tables,part throttle cruising and WOT etc.

 

[Schurkey]

Code 15 ecm detects low coolant levels.
I do not know since I didn't think these ecms could detect coolant levels.

Not low coolant level. Low coolant TEMPERATURE level.

Connect a scan tool, see what temperature the computer thinks the engine is running. Somewhat common for failed CTS or CTS wire harness to show temps around -40.

Code 43 is esc intermittent short to ground in the bypass circuit. Sounds like you got either a short to ground or the computer can't detect the pathway to the distributor. Cuid be a bad pick up coil or icm or the distributor has a lot of play and is worn.
I've delt with oil getting up into the EST distributor before and shorting the icm and pick up coil. But that can't be since your distributor is rusty.

I'd be looking for knock-sensor problems, or the wire harness from knock sensor to ESC/Computer.

Connect a scan tool, look for knock counts. Especially, tap the iron cylinder head or block with a small hammer. If the knock sensor doesn't trigger a knock count, (which will retard timing and slow the engine idle speed) there's problems.

Code 44 is o2 sensor for lean condition . This is probably due to the lines filter being closed with whatever that crud is.

FIFY. That's my guess, too.

 

[short1500]

Don't really have a computer to use so what do you think about the OTC 3211 or actron cp9690?

 

[short1500]

Waiting on my red devil cable in the mail. Hope I can get this damn truck figured out.

 

[short1500]

Ok so not sure what I need to be looking for because I'm not familiar at all with this stuff bet here are some pics and videos. It's doing some new stuff now. In gear the idle jumps way up. Won't let me upload video.Anyway any help is appreciated. I need to get this going.

 

[Schurkey]

Stop looking at the "RAW data" tab. It's useless until converted into a number that means something. "Sensor data" would be enormously better.

Seems like the IAC doesn't move.

Battery voltage seems a bit low.

"Rich Lean counter" is--apparently--what I'd call "cross-counts" of the O2 sensor. Number is WAY higher than I'd expect. Maybe an artifact of the scan tool, not the actual computer/sensor system.