Co0ke Posted August 14, 2013 Author Share Posted August 14, 2013 Found out today that my leak down is normal and I think it is a little slower after installing the new injectors. I think it's safe to assume the fuel system which is all new at this point is not the culprit. My problem remains that heating up is causing now, not only bad idle, but stumbling on the gas too. I barely made it 7 miles to home from work today. The car ran fine for a bit then at 45mph cruising in 5th; a hiccup ....another hiccup... A few more, then stumbling. I can kick the clutch and rev it to win back some decent operation ....but with time it just keeps getting worse. Eventually, the car will stumble almost constantly and revving the engine can barely keep it alive. It's never quite been right but it has slowly gotten worse. Before I broke down I was able to take 30 minute drives through neighborhoods without worrying. Now I'm afraid it will die if I try to go 5 miles. Have the next three days off and I'm determined to find the problem!! Quote Link to comment Share on other sites More sharing options...
tooquick260 Posted August 14, 2013 Share Posted August 14, 2013 Do you have a gauge on your fuel system? Just to verify you are getting gas. Is the pump good? Sounds more like a fuel delivery issue. Quote Link to comment Share on other sites More sharing options...
Co0ke Posted August 15, 2013 Author Share Posted August 15, 2013 (edited) Yeah I have a gauge, readings are good at idle and on the gas ...can't remember the exact numbers but its spec. I'm convinced its an electrical issue at this point ....something is getting hot and failing. Tested the MAF and it saw good numbers, cold and hot when the car started acting up. Tested the coil and BINGO! Way off 45 kohms....supposed to be 8.5 -12.5. Luckily I had a spare from the 260, popped it in there and what do ya know? Same exact issue!! Literally no improvement. Didn't have time to check anything else. My guess is ignition module or CAS. If I get a chance I'll take a vid tomorrow. Edited August 15, 2013 by Co0ke Quote Link to comment Share on other sites More sharing options...
NewZed Posted August 15, 2013 Share Posted August 15, 2013 My problem remains that heating up is causing now, not only bad idle, but stumbling on the gas too. I barely made it 7 miles to home from work today. The car ran fine for a bit then at 45mph cruising in 5th; a hiccup ....another hiccup... A few more, then stumbling. I can kick the clutch and rev it to win back some decent operation ....but with time it just keeps getting worse. Eventually, the car will stumble almost constantly and revving the engine can barely keep it alive. Is the ECU getting the right temperature signals? Engine runs good when cold with rich air/fuel mixture, terrible when hot and super-rich. Check at the ECCS plug. Quote Link to comment Share on other sites More sharing options...
Co0ke Posted August 15, 2013 Author Share Posted August 15, 2013 Checked the ECCS plug and got normal readings from the CHTS and the air temp sensor. My plugs aren't fouled either. Quote Link to comment Share on other sites More sharing options...
Co0ke Posted August 16, 2013 Author Share Posted August 16, 2013 OK, here is a video of it running.... I also went ahead and pulled the plugs just to check em again since I hadn't in a few days and all fouled? might be coincidental since I was messing around with the MAF a lot this afternoon ...but not so sure hmmm. Quote Link to comment Share on other sites More sharing options...
Co0ke Posted November 1, 2013 Author Share Posted November 1, 2013 Been awhile since I updated. Cars been on timout due to the frustration its caused me all summer. Couldn't get any help on the electrical forum for my ignition problem. I somehow just lost spark all together and couldn't figure out why. I noticed the green light on the ECU was staying lit while cranking and that didn't seem right. No one in the electrical forums responded when I asked the question why that might be so I figured no one had experience with it. I tested just about every pin and found that the ignition signal pin wasn't reading while cranking. Put in a new GM module and Coil but no luck. Went to the junk yard and got a CAS out of a 92 Maxima, no luck, but green light turns off when cranking. figured something was up and wasn't ready to condem the computer. I did have the key in the on position for a long time right after I installed the new module and thought maybe I fried the coil and/or module. New coil; no luck. New module. BAM spark! Still has a major cold start problem, under the impression its fuel related as my fuel is still bleeding back rather quickly IMO, maybe some air getting in the line. Basically the entire ignition system is new minus the computer. Drove around the block today for a good 20 minutes while the engine was nice and hot and it kept on running! Not a perfect idle but it didn't stutter and die! So a win for now Hopefully this problem is behind me and I can move forward with my build! More to come. Quote Link to comment Share on other sites More sharing options...
tooquick260 Posted November 1, 2013 Share Posted November 1, 2013 Wow sorry about your struggles. Didn't see or read about this issue. I don't know how I missed that. Glad you got it figured out. I was on a big downward spiral with my z31 ecu install. All self inflicted. I am driving everyday now. Running the 500cc inj, Z32 maf 8lbs boost daily and flip the switch for 12lbs when I want now that the couplers are staying on. Planning body work. Quote Link to comment Share on other sites More sharing options...
Co0ke Posted November 2, 2013 Author Share Posted November 2, 2013 I definitely learned a lot. Was going to go for the z31 ECU and will most likely when I'm ready to turn the boost up. Just trying to get her reliable, still need to fab up my exhaust and mount my boost gauge somewhere. Hope the body work goes well. Much more straight forward then trouble shooting electrical issues Quote Link to comment Share on other sites More sharing options...
Co0ke Posted November 6, 2013 Author Share Posted November 6, 2013 Found out my distributor was off a tooth and that was why it felt/sounded like it was firing too early when trying to start. Drove around the neighborhood making tons of noise as I'm still running an open down pipe since it wasn't reliable enough to get to the muffler shop all summer. One thing I noticed was while it was cool for about a minute idle sucked, warm the idle sat at a nice 750, then once hot the idle went to 1100 and stayed there with a little miss .....not sure what explains this but I'm happy it's running Quote Link to comment Share on other sites More sharing options...
Co0ke Posted November 11, 2013 Author Share Posted November 11, 2013 Took a drive today and she was sluggish....guessing its because I set the timing back to 19-20.... Gonna re-check it tomorrow definitely had more pop before I moved the distributor back one tooth Quote Link to comment Share on other sites More sharing options...
NewZed Posted November 11, 2013 Share Posted November 11, 2013 Found out my distributor was off a tooth and that was why it felt/sounded like it was firing too early when trying to start... Didn't you check the timing with a light? The distributor's position determines where the rotor is when the spark happens but if the spark's not jumping to the wrong terminal (which would cause a bad miss), what tooth it's on shouldn't matter if the timing is right. Just saying, the logic seems off a little bit. Quote Link to comment Share on other sites More sharing options...
Co0ke Posted November 12, 2013 Author Share Posted November 12, 2013 (edited) Timing was close but I couldn't dial it back below 26 degrees btdc. Moving it one tooth back let me put it at 20 where it should be. That 6 degrees helped a lot when starting the car Edited November 12, 2013 by Co0ke Quote Link to comment Share on other sites More sharing options...
Co0ke Posted November 25, 2013 Author Share Posted November 25, 2013 Got my exhaust system fabled up today! Used 2.5" to get to the tranny tunnel then bumped up to 3" all mandrel bends. The pipe expander did fine on the 2.5" pipes but almost striped the threads trying to expand the 3"ers. So I used a coupler on the last two elbows before the dynomax ultraflow. Video to come soon on the sound:). Super thankful to my awesome neighbor for the use of his expertise, welding skills, and general willingness to help! Pics below are of the new starter, old ones brushes were so worn the shoes ate away at the copper, the boost gauge location, for now, thought I might like it down by my right leg but its too far from a quick glance, and the GM module. Also put in new injector wires, still chasing a misfire....me and the neighbor made a smoke machine to check for a vacuum leak as I'm running out of ideas. Maybe ill show a vid of that as well. Till next time. Quote Link to comment Share on other sites More sharing options...
Co0ke Posted December 1, 2013 Author Share Posted December 1, 2013 Ok here's a few quick vids. Not the greatest. Will do a ride along soon. My driveshaft was way out of balance as well as my wheels, after fixing those she is such a freaking joy to drive now. Took her around a few twisties yesterday with a big smile on my face. The overwhelming sense of accomplishment, plus the fact that this is the fastest car I've owned and I built it, is just f$&@ing cool. Took the bumpers off, removed all the rubber on the front and collapsed the shocks so it now sits snuggly against the nose, leaving the rear off. Ill remove the bumper shocks from the rear when I feel like dropping the tank.... Quote Link to comment Share on other sites More sharing options...
tooquick260 Posted December 2, 2013 Share Posted December 2, 2013 Looks great.... Like the bumpers tucked in! Quote Link to comment Share on other sites More sharing options...
Co0ke Posted June 29, 2016 Author Share Posted June 29, 2016 Well, it has been a long time. But I'm back. Since my last post I haven't done much but enjoy driving the 260 for what it was. Plenty of fun and turns heads wherever I go. I have been planning to do much more like: Megasquirt, fender flares, wider wheels, replace all bushings, all the updates need to turn up the boost. Just haven't been able to with job change, lack of funds, life, etc. However, my business is running pretty well these days and with the sale of my house I am free to start working on the Z again. Excited to do it! I just procured Megasquirt! Now to start deleting unnecessary crap off my intake, install all the needed sensors and hook up my intercooler. Right now I'm looking at the following -Megaquirt 2 v3.57 from diyautotune -GM IAT sensor w/ pigtail -using stock CHTS -10' wiring harness from DIYAutotune -Innovate wideband -trigger wheel for 83 distributor from DIYautotune -Rx-7 TPS (my brother has an extra so I will try it for fitment) I have already started ripping stuff off the intake. Going to use the 280zxt one for now then upgrade to I cleaner setup with the intake and fuel rail once I have everything working. Also, since this is my first rodeo with megasquirt and cleaning up my intake I'll be doing things in stages and test/checking as I go so as not to get too far ahead of myself and waste time backtracking to try and figure out where I went wrong. Quote Link to comment Share on other sites More sharing options...
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