Hey Guys, New to forum. Have searched.

Background: I'm a jeep guy with a love/hate for TPI's. In the Jeep CJ7 I Have a stock 5.7 from an 87 Camaro along with 700r4.

Problem: Getting code for knock sensor code, engine runs shizy in upper RPM's, cuts out.

(Prior to this all with in the month, New complete dizy from DUI, new live wires, new AC Delco plugs, new TPS,(set with multi meter) New idle control valve, new bosh 4 hole injectors. I did all of this as most of the stuff was original, and needed freshen, as I am planning a long jeep outing)

Big problem: I have used A/C Delco Knock sensor part #10456288, I have tried Napas, BWD, and a few more. Basically thrown 5-6 different new knock sensors all agedly for my year.

Tests: 5 volts from knock sensor wire, tested old knock, getting 3.9k resistance from multi-meter. New Kocks all getting 100k? any ideas?

 

TPI knock sensors should be 3.9k.

The knock sensor being bad will not cause the engine to cut out or misfire. It just won't detect detonation and retard timing accordingly.

What is your BLM and INT? Have you checked fuel pressure? Done a VE calculation? Here's a good one that I use:

https://atgtraining.com/atg-volumetr...cy-calculator/

GD

 

Tpi maf is 100k knock sensor
lean int/blm ?

 

That was my understanding on the 3.9k ohms on resistance, this is my problem, I cant find one. Possibly get one for a corvette maybe 1985? No MAF, the fuel pump is external Bosch 4404, been running it in the car for years, replaced it with new one, same results. I have about 30+ psi according to my chep-O liquid pressure gage on the fuel rail, however it has maintained that reading for quite some time, including when the car was running great. Possible fuel pressure reg? The car sputters in high rpm, under load, when I disconnect the knock, it make it worse, sputters almost consistently. Tested all fuel injectors with multi meter, getting about 16-17 ohms on all of them. FYI, with new dizzy timing was set with ECT unplugged, at 6deg BTDC, then engine turned off, and plugged back in.

 

87 should be MAF and it appears I was wrong on the resistance. Are you SURE this isn't an SD TPI setup? Which computer is it running? 7730 or 7165?

GD

 

the mention of no maf could be a 1227727 or 1227730 a picture of the ecm would help.

 

 

 

best I could do without surgery

 

looks like I have the bottom left

 

That’s a 1227730 90-92 speed density ecm.
you might datalog with tunerpro rt $8d adx file.
did this start to happen after the injector change ?

http://web.archive.org/web/202002070...hunder.com:80/

 

Yup. That harness and ECM is from a 90-92 F-body. You're intake might have come from an 87, but your electrical didn't.

As Tuned Performance suggests - you need to interface with the ECM and find out what it's doing for fueling and timing, etc. You can't effectively troubleshoot computerized fuel injection without considering the computer and finding out what it's doing.

GD

 

Injectors were replaced about 6 months ago, The vehicle ran fine, I'm hard on it off-road a lot of full throttle blips. I was just driving down the road and all of a sudden it started to sputter under load, that's when I put in new fuel pump (I carry 2 all the time as spares, I run a fuel cell with external pumps), I had NIB waiting to go in, MAP, Idle control, TPS, and a a complete Chevy DUI dizzy. with I popped off the cap of old A/C Delco dizzy, it looked like the internals were falling apart. So I shot gun all the new parts at it, set up my TPS with a multi meter, assuming I had a 1987 5.7. I ran the codes with a paper clip and got the knock sensor code 43 (4 quick flashes followed by three). So apparently I am buying the wrong knock sensor, but I'm not sure if that's the extent of my problem as I'm learning about this motor. so do I buy a data cable for OBD1 and run software on my laptop? if so what do you guys recommend, if you could spell it out in lame **** turn lol as I'm new to this motor and more a builder fabricator, not a mechanic, but a quick study, and computers are my friend.

Here are some number on the motor, ill get the date stamp with a mirror today
block #? 14093638 located on pass side of motor on back lip of Block
5.7 LG SGT but maybe my T is an I SGI (diver side lip near dizzy)

 

 

Just a 10 ft. view

 

This is the cable you need:

https://www.moates.net/aldu1-and-cabl1-p-127.html

And this is the software:

https://www.tunerpro.net/

Here is all the data-stream definition files, etc:

http://www.gearhead-efi.com/Fuel-Inj...Information-8D

GD

 

Thank You!, so I pulled the date code off the block E132. my understanding is E=May 13= the 13th and 2= is 1992? As the 92 fits in the block casting date ranges 14093638. Am I correct on this?

 

I guess whtn you throw 1987 parts ant a 1991-92 motor and computer, this is some disagreement lol.

 

Most of the parts are the same actually. The knock sensor wouldn't cause your main issue. The 90-92 does have a MAP sensor and perhaps that has an issue but it's really hard to know till you understand what the computer is seeing.

I don't think it makes any difference what the engine is as far as year or what it came from. It's a small block with center bolt valve covers so it's an 87+ roller motor.

It is odd that the intake doesn't have the bracket for the MAP sensor.

GD

 

Optical illusion or is the tps disconnected?

 

It was disconnected in the pic, I was in the middle of a multi meter test

 

UPDATE:
1st...Thanks to all's advice.
2. replaced knock, car runs 90% better, instead of sputtering under any kind of load, it rips in the upper RPM, check engine light off.

What it is doing now is from a dead stop, if I floor it, it sputters, sounds like misfire, then once RPM's are up is runs fantastic, if I keep the R's up is runs good. I'm going to order the cable and download the software, it is a must have tool for sure. what about the fuel pressure regulator? I have replaced the injectors from south bay, but do pressure regs go bad? maybe my injectors not getting or too much fuel at injectors? thoughts?

 

Regulators can go bad , pull off the vacuum line to is and check for fuel.

 

Sorry for butting in. High rev cutout under load is very likely ignition KV breakdown, usually the coil. It's often a costly mistake to assume just because a part is new that it's okay. Pull the coil cover and the coil. Take a look at the anode from the coil to the rotor. Does it all look okay? Try a different coil.

 

So to hopefully put a soft close on this thread, I purchased a spark/arch tester. I warmed the engine up to operating temp, put in the tester and set it to 40, no arch. closed the gap to 30, intermittent arch. I only got continuous arch when it was set below 30, upper 20's. Form searching, I gather I need or should be hitting 40 no problem correct? so I'm going to replace plugs(I have a set already? and replace coil with a A/C Delco unit and test again.

 

Just tighten up your spark gaps. There's no significant benefit to running huge gaps. Gap them all to .020" and run it. Puts a lot less strain on your ignition components.

GD