Ωhm Posted May 5, 2020 Share Posted May 5, 2020 On 5/5/2020 at 1:48 AM, SoCalManche said: I also just picked up a noid light set to verify pulse on the injector harness, and it does light up when i switch key to ON, as well as crank. Expand Shouldn't noid light flicker during CRANK? On 5/5/2020 at 2:15 AM, SoCalManche said: Where do I ground? Expand Any good ground point will do. Link to comment Share on other sites More sharing options...
SoCalManche Posted May 5, 2020 Author Share Posted May 5, 2020 On 5/5/2020 at 2:16 AM, Ωhm said: Shouldn't noid light flicker during CRANK? Any good ground point will do. Expand T3 = 12V. Noid light is bright when key ON; noid light dims when cranking. Link to comment Share on other sites More sharing options...
Ωhm Posted May 5, 2020 Share Posted May 5, 2020 On 5/5/2020 at 2:25 AM, SoCalManche said: T3 = 12V. Expand Good reading. On 5/5/2020 at 2:25 AM, SoCalManche said: Noid light is bright when key ON; noid light dims when cranking. Expand Dimming makes you think INJ should be firing. Link to comment Share on other sites More sharing options...
SoCalManche Posted May 5, 2020 Author Share Posted May 5, 2020 On 5/5/2020 at 2:33 AM, Ωhm said: Good reading. Dimming makes you think INJ should be firing. Expand Is there anyway my fuel pump is shot even though it will immediately engage with jumper wire? Link to comment Share on other sites More sharing options...
Ωhm Posted May 5, 2020 Share Posted May 5, 2020 On 5/5/2020 at 2:35 AM, SoCalManche said: Is there anyway my fuel pump is shot even though it will immediately engage with jumper wire? Expand I don't think so, not with 15psi. Link to comment Share on other sites More sharing options...
SoCalManche Posted May 5, 2020 Author Share Posted May 5, 2020 On 5/5/2020 at 2:37 AM, Ωhm said: I don't think so, not with 15psi. Expand Any thoughts then? Link to comment Share on other sites More sharing options...
Ωhm Posted May 5, 2020 Share Posted May 5, 2020 ECU are pricey, especially when it don't fix your problem. Link to comment Share on other sites More sharing options...
SoCalManche Posted May 5, 2020 Author Share Posted May 5, 2020 On 5/5/2020 at 2:42 AM, Ωhm said: ECU are pricey, especially when it don't fix your problem. Expand Ha, completely agree. Do you think ECU is fried? Link to comment Share on other sites More sharing options...
eaglescout526 Posted May 5, 2020 Share Posted May 5, 2020 (edited) Try anywhere inside the cab that touches the sheet metal. Also doing the resistance test on the injector should say something. Since you had the injector unplugged for the light test, take one lead and put one on one injector post and the other on the other post and see if it has more or less than 10 ohms resistance. Ok I missed this new page, disregard what I said. Edited May 5, 2020 by eaglescout526 Link to comment Share on other sites More sharing options...
eaglescout526 Posted May 5, 2020 Share Posted May 5, 2020 Well, trying to help prevent ya from buying a new ECU. Not sure what the return policy is at parts stores on if the ECU fixes your problem or not. Buuuuuttt if we go the ECU route send @70barracuda a PM about a 2.5L ECU. I am buying his old one off of him and he could probably send the ECU to you for testing purposes. Link to comment Share on other sites More sharing options...
SoCalManche Posted May 5, 2020 Author Share Posted May 5, 2020 On 5/5/2020 at 2:49 AM, eaglescout526 said: Try anywhere inside the cab that touches the sheet metal. Also doing the resistance test on the injector should say something. Since you had the injector unplugged for the light test, take one lead and put one on one injector post and the other on the other post and see if it has more or less than 10 ohms resistance. Ok I missed this new page, disregard what I said. Expand Well don't worry about it, because I didn't know you could test the injector that way. It maintains a 1.4 ohms or so. Link to comment Share on other sites More sharing options...
eaglescout526 Posted May 5, 2020 Share Posted May 5, 2020 On 5/5/2020 at 2:56 AM, SoCalManche said: Well don't worry about it, because I didn't know you could test the injector that way. It maintains a 1.4 ohms or so. Expand Well theres a $100 you don't have to spend. I don't think those injectors ever go bad but they are just GM injectors. Link to comment Share on other sites More sharing options...
SoCalManche Posted May 5, 2020 Author Share Posted May 5, 2020 On 5/5/2020 at 2:53 AM, eaglescout526 said: Well, trying to help prevent ya from buying a new ECU. Not sure what the return policy is at parts stores on if the ECU fixes your problem or not. Buuuuuttt if we go the ECU route send @70barracuda a PM about a 2.5L ECU. I am buying his old one off of him and he could probably send the ECU to you for testing purposes. Expand Wow, I would appreciate that immensely. When is he supposed to send it out? Link to comment Share on other sites More sharing options...
eaglescout526 Posted May 5, 2020 Share Posted May 5, 2020 On 5/5/2020 at 2:58 AM, SoCalManche said: Wow, I would appreciate that immensely. When is he supposed to send it out? Expand No idea. Just sent him a PM talking about it, he's pretty good about getting back to me. At the moment he isn't sending the parts out yet but I can't make a promise on how quickly he can get the ECU out Link to comment Share on other sites More sharing options...
SoCalManche Posted May 5, 2020 Author Share Posted May 5, 2020 On 5/5/2020 at 3:00 AM, eaglescout526 said: No idea. Just sent him a PM talking about it, he's pretty good about getting back to me. At the moment he isn't sending the parts out yet but I can't make a promise on how quickly he can get the ECU out Expand We have a Jeep-focused JY out here called Hardrock 4x4, and I'll call in the morning to see what they are charging for ECUs. Would there be anything we may have skimmed over before taking the plunge in this direction? Link to comment Share on other sites More sharing options...
eaglescout526 Posted May 5, 2020 Share Posted May 5, 2020 Not that I can think of. Starter relay/solenoid is good as the engine cranks, ECU pulses the injector, injector is good on the resistance, spark comes from the coil, CPS tests alright, FP runs with good pressure, good bat voltage, fusible link to pin 30 for FP relay is good, ignition switch is good, engine fires with fuel down the TB. The only thing we absolutely don't know about is the MAP and the TPS. Link to comment Share on other sites More sharing options...
SoCalManche Posted May 5, 2020 Author Share Posted May 5, 2020 What do I need to attack on those to rule them out? Link to comment Share on other sites More sharing options...
eaglescout526 Posted May 5, 2020 Share Posted May 5, 2020 We tried the tests for them and came up with bizarre results. We never got the 5V to the sensors from the ECU so theres something wrong somewhere and it all just might boil down to the 5V circuit. Link to comment Share on other sites More sharing options...
SoCalManche Posted May 5, 2020 Author Share Posted May 5, 2020 On 5/5/2020 at 3:14 AM, eaglescout526 said: We tried the tests for them and came up with bizarre results. We never got the 5V to the sensors from the ECU so theres something wrong somewhere and it all just might boil down to the 5V circuit. Expand I just came across the TPS adjustment test randomly on a different forum. With key ON, the resistance seems to be switching back and forth between 0 ohms and O.L. Power probe to (B), Ground probe to Neg Batt; TPS harness disconnected from TPS. Is that correct? Link to comment Share on other sites More sharing options...
SoCalManche Posted May 5, 2020 Author Share Posted May 5, 2020 That TPS is really aggravating. Even plugged in, and regardless if key ON or OFF, it reads weird, roughly around ~100mV. Link to comment Share on other sites More sharing options...
eaglescout526 Posted May 5, 2020 Share Posted May 5, 2020 Is it a Jeep forum? The adjustment is this: Key on engine off Check sensor input voltage, Connect negative lead to TB and positive to TC Note here is to not unfasten the sensor nor unplug it from the harness but back probe the connector. Move the throttle plate to wide open, be sure throttle linkage contacts the stop Note the reading for the input voltage for B and C should be 5V wide open Return throttle plate to resting. Check sensor output voltage by taking positive lead from TC and put it in TA. Move and hold the throttle plate wide open like testing the input voltage. Note this entire adjustment is with the throttle plate wide open so it will be a bit tough to do alone but it gets easier the more times it is done. Voltmeter reading should be 4.6-4.7VDC, adjust the output as necessary. Loosen the bottom retaining screw for coarse adjustment and loosen the top screw for fine adjustment until the output has hit between 4.6-4.7VDC and then tighten the screws while holding the sensor still during tightening. Link to comment Share on other sites More sharing options...
SoCalManche Posted May 5, 2020 Author Share Posted May 5, 2020 On 5/5/2020 at 3:27 AM, eaglescout526 said: Is it a Jeep forum? The adjustment is this: Key on engine off Check sensor input voltage, Connect negative lead to TB and positive to TC Note here is to not unfasten the sensor nor unplug it from the harness but back probe the connector. Move the throttle plate to wide open, be sure throttle linkage contacts the stop Note the reading for the input voltage for B and C should be 5V wide open Return throttle plate to resting. Check sensor output voltage by taking positive lead from TC and put it in TA. Move and hold the throttle plate wide open like testing the input voltage. Note this entire adjustment is with the throttle plate wide open so it will be a bit tough to do alone but it gets easier the more times it is done. Voltmeter reading should be 4.6-4.7VDC, adjust the output as necessary. Loosen the bottom retaining screw for coarse adjustment and loosen the top screw for fine adjustment until the output has hit between 4.6-4.7VDC and then tighten the screws while holding the sensor still during tightening. Expand Alright man, something is wonky here. Opening throttle, regardless of how much, does not affect the voltage readout. With that said: - TB & TC = 3.4V. Again, wide open throttle retained 3.4V. - TA & TB = -50mV the first time, and then ~100mV the second time. Throttle position did not matter. All of this is plugged in, key ON. I also shook the engine harness to check wire integrity while plugged into TB & TC, and no fluctuation occurred. Retained 3.4V. Link to comment Share on other sites More sharing options...
eaglescout526 Posted May 5, 2020 Share Posted May 5, 2020 That’s why we never did the adjustment because of the MAP sensor 5V. Something is bizarre so I am not certain if a new ECU will rectify the 5V problem. Link to comment Share on other sites More sharing options...
SoCalManche Posted May 5, 2020 Author Share Posted May 5, 2020 On 5/5/2020 at 3:49 AM, eaglescout526 said: That’s why we never did the adjustment because of the MAP sensor 5V. Something is bizarre so I am not certain if a new ECU will rectify the 5V problem. Expand Damn, well you guys already know that if you're out of ideas, that leaves me to be way lost, ha. Link to comment Share on other sites More sharing options...
eaglescout526 Posted May 5, 2020 Share Posted May 5, 2020 I mean honestly the only person in the world I know who has the MS1700 is nickintime and I happen to have an ECU tester and so do 30 people on eBay. But the only absolutely last thing is the ECU and wiring harness. Link to comment Share on other sites More sharing options...
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