Car dies randomly

Hello, it's me again. Long annoying embarrassing story about my drive home from work. 92 vr4, maft gen2 w/ gm maf, 9bs, 360cc inj, wideband, afpr, 5 gauges, fmic & hotwired walbro.

My car recently just started completely dying at random times. For instance, this morning driving to class, I turned onto a street and the engine just cut out completely, rpms dropped and everything. Then it caught itself and rpms came back up and I continued my drive. Again after work when I let it warm up, about a minute after letting it idle, the rpms cut out, idle dropped very low very fast, then it caught itself and it idled just fine. Driving home is where it started getting bad. I was getting on the highway in 3rd then the engine cut out. The rpms dropped to 0 but i was still trying to gas it to see if i could get it to keep going, then i got a huge backfire from under the car, then it died. This happened about 10 more times within a mile of my house, but only backfired twice. I got to a light and the car kept dying over and over, but started up everytime. I'd drive and get about 50ft then it would die again. I finally got into my driveway and the car died again. I kept restarting it and running to the hood, and checking the wiring but nothing I found could replicate the dying, it was completely random. About the 3rd or 4th time it died, it wouldnt restart. Just cranked forever until I let it set for a few minutes, then it would start and die within seconds everytime I tried to get it to idle.

This is just an anytime problem not just during idle, cruise, or boost.

This all started happening this morning so I'm just trying to find out where to start with this. I noticed it began when I was low on gas this morning, and got a little better after filling up. The way the rpms drop randomly and the car would just crank, I'm leaning towards a fuel pump, cam/crank sensorr, IAC right now. The car runs perfect other than this problem.

Hate the no idle. Isc/iac check 4 sure...I had the no idle. Maf tested fine per manual. After changing coil,ptu,& doing other maintainenance, that was good, but unrelated to problem; finally changed out maf which solved issue.

connected via tapatalk

I forgot to mention it started happening when I was low on gas too. I just remembered I filled up this morning. Hotwired Walbro. The isc is about a year old but I'll check it anyway. No idle is embarrassing espcially with a loud exhaust so everybody thinks I stalled it.

Ok I couldnt deal with sitting here thinking about what it could be so I went out to the car barefoot with a multimeter to check batt voltage and lo and behold, loose ground terminal :Doh: Car should be good now hopefully. I have no problem fixing customer cars, but I never think logically with my own. Then again, most customer cars don't spin bearings and lock up transfer cases. :rolleyes3:

Well started it uo this morning and the rpms still drop during during start but it didn't die yet. I'll see how far I get.

The car died down the road.rpms fell to 0 for a few seconds then the car came back to life.

Bump. I tightened and cleaned the battery terminals and the car died this morning driving to class. A few minutes ago I tested the ISC and it tested fine since its basically brand new. But the car is still stalling out very calmly like the ignition is being turned off. When it dies the radio and lights still work and it usually will start back up then die again, or just crank. The ecu is also a rebuilt from oreillys, not even a year old. I havent checked the ptu or CAS yet so does anyone know the procedure to test the CAS?

Bump for help

I'm pretty sure I found the problem. One of the female plugs on the harness side of the coil pack was broken. The little tab on the inside of the ground wire (harness plug) that's supposed to be bent inward to contact the male prong was broken. The male prong on the coil pack was basically going into a hollow tube and not making good contact with any sides of that plug. I was able to control the car shutting off by wiggling the plug up or down. I'll solder in a new plug when I get one, but im 100% sure this is the problem. I'll check back in case this doesnt fix it. But check your plugs out every now and then.

If you are still having issues after fixing coil, try trading out your GM MAF with a known good one.

http://i986.photobucket.com/albums/a...mChecklist.jpg

My '94 TT has been cutting out recently. It usually happens within the first two miles of a cold start, though it has happened a few times when at full operating temperature 30 miles / minutes into a trip. Here's what it looks like when logging:

Code:

Normal deceleration: Time RPM Knock O2vF O2vR IPW TPS Trim Load Timing AirFlow IDC Boost 320.16 1500 0 0.00 0.00 0 10 100 8 19 31.45 0 -11.48 320.43 1500 0 0.00 0.00 0 10 100 8 19 31.45 0 -11.29 320.66 1500 0 0.00 0.00 0 10 100 8 19 31.45 0 -11.48 320.92 1500 0 0.00 0.00 0 10 100 8 19 37.74 0 -11.48 321.14 1469 0 0.00 0.00 0 10 100 9 19 37.74 0 -11.48 321.41 1469 0 0.00 0.00 0 10 100 9 19 31.45 0 -11.29 321.64 1469 0 0.00 0.00 0 10 100 9 19 31.45 0 -11.29 321.9 1469 0 0.00 0.00 0 13 100 9 18 37.74 0 -11.09 322.12 1469 0 0.00 0.00 0 15 100 12 18 44.03 0 -10.51 Easing back into the throttle: Time RPM Knock O2vF O2vR IPW TPS Trim Load Timing AirFlow IDC Boost 322.38 1438 0 0.00 0.00 1.536 16 80 13 18 50.32 2 -10.12 322.61 1438 0 0.00 0.00 1.792 18 101 20 24 62.9 2 -9.54 322.9 1469 0 0.04 0.04 2.304 18 108 22 28 69.19 3 -8.95 323.11 1438 0 0.06 0.06 2.304 18 113 23 28 69.19 3 -8.76 323.36 1406 0 0.06 0.08 1.792 18 119 13 27 56.61 2 -8.56 323.6 1438 0 0.02 0.02 1.792 19 80 12 28 37.74 2 -7.98 Here's where it cuts out. TPS shows that I am modulating the throttle. Load and Airflow suggest that MAF is working. IPW suggests that ECU is calling for fuel. O2v suggests that there is no combustion. Trim values are odd. Time RPM Knock O2vF O2vR IPW TPS Trim Load Timing AirFlow IDC Boost 323.86 1406 0 0.00 0.00 1.28 19 80 8 28 37.74 1 -7.59 324.08 1375 0 0.00 0.00 1.536 19 80 9 27 31.45 2 -7.59 324.37 1375 0 0.00 0.00 1.28 21 80 9 27 44.03 1 -6.42 324.6 1375 0 0.00 0.00 1.536 30 80 11 27 37.74 2 -1.75 324.86 1344 0 0.00 0.00 1.28 40 80 21 27 50.32 1 -0.39 325.07 1313 0 0.00 0.00 2.048 47 80 13 27 37.74 2 0.00 325.35 1344 0 0.00 0.00 1.28 56 100 22 27 50.32 1 0.20 325.59 1344 0 0.00 0.00 1.792 65 100 13 27 37.74 2 0.20 325.87 1313 0 0.00 0.00 2.816 14 80 12 27 37.74 3 -6.81 326.09 1313 0 0.00 0.00 1.536 16 80 9 27 31.45 2 -7.98 326.36 1344 0 0.00 0.00 3.584 35 101 20 28 44.03 4 -0.58 326.59 1250 0 0.00 0.00 1.792 45 80 11 27 37.74 2 0.00 326.86 1344 0 0.00 0.00 2.56 14 102 14 26 44.03 3 -5.45 327.08 1313 0 0.00 0.00 1.792 15 80 11 27 37.74 2 -7.78 327.35 1344 0 0.00 0.00 2.56 38 102 15 28 44.03 3 -0.19 327.57 1250 0 0.00 0.00 1.792 44 80 12 26 69.19 2 0.00 327.85 1313 0 0.00 0.00 3.84 18 107 43 25 88.06 4 -4.09 Everything abruptly returns to normal: Time RPM Knock O2vF O2vR IPW TPS Trim Load Timing AirFlow IDC Boost 328.07 1406 0 0.04 0.04 2.816 15 114 28 28 75.48 3 -7.78 328.45 1375 0 0.76 0.06 5.12 32 122 53 21 150.96 6 -0.39 328.69 1375 0 0.82 0.80 5.12 37 114 62 20 157.25 6 -0.19 328.97 1406 0 0.74 0.70 5.12 38 105 64 20 169.83 6 0.20 329.19 1406 0 0.68 0.53 5.12 38 105 65 20 201.28 6 0.59

So I assume there is fuel but no spark. ProwlerGT's Sensor Review / Sputter and Hesitation Troubleshooting Guide is an excellent resource and I'm looking for suggestions on where to start. The O2 sensors, plugs, wires, coil packs and FP relay are all relatively new. I don't suspect the TPS since I'm seeing values in the log (and I don't suspect the ISC / IAC Servo since it happens off idle). Is the CAS a likely culprit? 2G ECUs don't suffer from leaky caps, right?

Today's log below. I didn't reformat the numbers this time since it's easier to see the problem this way (O2V should be 0 only when IPW is 0).

Code:

Time RPM Knock O2vF O2vR IPW TPS Trim Load Timing AirFlow ISC IDC Boost 230.78 1688 0 0.0585 0.078 1.536 15 80 13 31 56.61 55 2 -11.09 231.08 1688 0 0.0585 0.2535 1.536 15 80 13 31 56.61 55 2 -11.09 231.33 1688 0 0.0585 0.078 1.536 15 80 13 31 56.61 55 2 -11.09 231.61 1688 0 0.0585 0.078 1.536 15 80 13 31 56.61 55 2 -11.09 231.86 1688 0 0.0585 0.0975 1.536 15 80 13 31 56.61 55 2 -11.09 232.13 1719 0 0.0585 0.078 1.536 15 80 13 31 56.61 55 2 -11.09 232.39 1688 0 0.0585 0.078 1.536 15 80 13 31 56.61 60 2 -11.09 232.67 1719 0 0.0585 0.078 1.536 16 80 14 31 62.9 55 2 -10.9 232.91 1719 0 0.0585 0.0585 2.304 19 101 21 30 81.77 55 3 -9.73 233.19 1688 0 0.039 0.1755 2.56 19 109 24 30 88.06 55 4 -9.34 233.42 1719 0 0.819 0.8385 2.816 21 104 28 30 75.48 57 4 -8.17 233.71 1719 0 0.1755 0.156 2.816 21 104 29 30 81.77 57 4 -7.98 233.95 1719 0 0.117 0.0585 2.048 21 112 21 30 56.61 57 3 -7.78 234.24 1719 0 0.0195 0 2.048 22 80 11 31 44.03 57 3 -7.39 234.48 1719 0 0 0 1.28 14 80 9 31 31.45 55 2 -9.15 234.78 1688 0 0 0 1.28 13 80 9 20 31.45 55 2 -11.09 235.02 1656 0 0.0195 0.0195 0 13 100 8 20 37.74 55 0 -11.29 235.32 1656 0 0 0 0 15 100 9 20 31.45 57 0 -10.9 235.57 1656 0 0 0 0 26 80 14 30 50.32 64 0 -5.25 235.87 1625 0 0 0 1.28 41 80 8 30 31.45 73 2 -0.78 236.11 1625 0 0 0 2.816 45 102 13 30 44.03 72 4 -0.58 236.42 1625 0 0 0 1.28 13 80 9 30 37.74 55 2 -8.76 236.68 1625 0 0 0 1.28 14 80 9 30 31.45 58 2 -10.32 236.96 1594 0 0 0 4.864 40 102 45 25 163.54 73 6 -0.78 237.21 1563 0 0.0195 0.0195 4.608 14 119 47 26 106.93 65 6 -6.23 237.54 1656 0 0.9165 0.9165 2.048 13 115 23 29 75.48 55 3 -10.51 237.78 1625 0 0.897 0.897 1.792 16 109 14 30 69.19 59 2 -10.32 238.1 1656 0 0.2535 0.2925 5.12 34 103 55 24 207.57 71 7 -1.36 238.35 1656 0 0.741 0.429 4.864 38 100 63 22 226.44 72 7 -0.58 238.67 1656 0 0.0195 0.0195 1.792 43 113 21 30 56.61 73 2 0 239.03 1656 0 0 0 1.024 14 80 3 29 18.87 55 1 -7.98 239.33 1719 0 0.0195 0.0195 3.84 34 101 17 30 56.61 72 6 -1.36 239.6 1688 0 0 0 3.328 47 80 13 31 44.03 73 5 -0.19 239.91 1750 0 0 0 3.328 15 100 0 6 0 56 5 -7.39 240.16 1813 0 0.0195 0.039 1.28 36 80 8 31 25.16 74 2 -0.78 240.44 1781 0 0 0 10.496 49 100 0 7 0 54 16 0 240.67 1813 0 0.9555 0.9555 8.704 34 100 0 6 0 53 13 -0.97 240.96 1844 0 0.8775 0.4095 0 15 100 10 22 62.9 64 0 -7.59 241.21 1781 0 0 0 2.048 13 101 16 22 62.9 55 3 -10.51 241.54 1813 0 0.8775 0.9165 1.28 15 80 10 32 50.32 55 2 -11.29 241.81 1813 0 0.8385 0.78 3.584 26 101 31 32 125.8 65 5 -6.03 242.14 1875 0 0.702 0.2925 5.12 39 105 61 24 257.89 73 8 -0.58 242.4 1906 0 0.078 0.741 5.632 45 112 69 22 289.34 74 9 0.39 242.74 1969 0 0.6825 0.6825 5.888 49 98 75 21 320.79 73 10 1.56 243 2000 0 0.7995 0.156 3.328 16 99 49 27 144.67 70 6 -6.23 243.31 2031 0 0.9555 0.9555 1.792 13 89 15 33 62.9 55 3 -10.51 243.6 2031 0 0.936 0.936 1.28 13 80 8 33 44.03 55 2 -11.87 243.92 2031 0 0.8775 0.858 0 13 100 9 23 44.03 55 0 -11.87 244.18 2063 0 0.0195 0.0195 0 13 100 9 23 44.03 55 0 -12.07 244.52 2063 0 0 0 0 11 100 9 23 44.03 55 0 -12.07 244.78 2063 0 0 0 0 10 100 9 23 37.74 55 0 -12.07 245.07 2063 0 0 0 0 10 100 9 23 37.74 55 0 -12.07 245.32 2063 0 0 0 0 10 100 9 23 37.74 55 0 -12.26 245.62 2063 0 0 0 0 10 100 9 23 37.74 55 0 -12.07 245.87 2031 0 0 0 0 10 100 9 23 37.74 55 0 -12.26 246.18 2063 0 0 0 0 10 100 9 23 37.74 55 0 -12.07 246.43 2031 0 0 0 0 10 100 9 23 37.74 55 0 -12.07 246.72 2031 0 0 0 0 10 100 9 23 37.74 55 0 -12.07 246.97 2031 0 0 0 0 10 100 9 23 37.74 55 0 -12.07 247.26 2031 0 0 0 0 10 100 9 23 44.03 55 0 -12.07 247.52 2000 0 0 0 0 14 100 8 23 50.32 55 0 -11.68 247.83 2000 0 0 0 0 16 100 10 23 56.61 55 0 -11.29 248.08 2000 0 0 0 0 16 100 12 23 62.9 55 0 -10.9 248.38 2000 0 0 0 0 17 100 13 23 69.19 55 0 -10.51 248.65 1969 0 0 0 1.792 18 80 14 27 69.19 55 3 -10.51 248.97 1969 0 0.039 0.039 3.072 25 103 28 33 106.93 61 5 -7.39 249.22 1969 0 0.6435 0.8385 2.56 15 105 26 33 88.06 56 4 -9.54 249.53 2031 0 0.858 0.741 1.536 13 80 10 33 50.32 55 3 -11.68 249.78 1906 0 0.273 0.858 1.28 15 80 10 31 50.32 56 2 -11.09 250.29 1531 0 0.039 0.0585 3.84 25 108 36 29 132.09 78 5 -5.25 250.55 1594 0 0.8385 0.819 3.84 27 101 50 25 150.96 81 5 -2.92 250.86 1594 0 0.6825 0.078 4.352 33 104 59 22 207.57 82 6 -1.16 251.13 1594 0 0.039 0.117 4.864 33 118 61 22 207.57 83 6 -0.78 251.43 1594 0 0.0975 0.741 4.864 33 107 63 21 213.86 68 6 -0.58 251.8 1594 0 0.7605 0.195 5.12 33 109 64 21 220.15 68 7 -0.39 252.09 1625 0 0.1365 0.624 4.864 33 100 64 21 226.44 68 7 -0.19 252.35 1656 0 0.819 0.624 5.12 33 108 65 22 226.44 68 7 0 252.68 1656 0 0.702 0.663 4.864 30 99 62 23 213.86 66 7 -0.97 252.93 1656 0 0.8385 0.8385 3.584 25 92 51 25 144.67 63 5 -2.92 253.21 1656 0 0.8775 0.7605 3.84 22 82 46 26 132.09 60 5 -5.64 253.57 1656 0 0.9165 0.897 3.328 19 73 32 30 88.06 57 5 -8.17 253.86 1656 0 0.8775 0.7995 2.304 18 64 26 30 81.77 54 3 -9.15 254.1 1656 0 0.8775 0.2925 2.304 18 63 23 30 75.48 54 3 -9.54 254.39 1656 0 0.702 0.117 2.048 18 73 21 30 56.61 54 3 -9.54 254.65 1625 0 0.039 0.039 1.28 18 80 8 30 37.74 54 2 -9.54 254.97 1625 0 0 0 1.536 18 80 8 30 31.45 54 2 -9.34 255.22 1594 0 0 0 1.024 15 80 9 30 37.74 55 1 -10.32 255.54 1625 0 0 0.0195 1.28 32 80 9 30 31.45 68 2 -2.33 255.78 1625 0 0 0 3.84 35 80 16 30 50.32 72 5 -1.16 256.09 1594 0 0 0 1.28 48 80 8 30 31.45 74 2 -0.19 256.33 1594 0 0 0 2.304 49 103 13 30 44.03 73 3 -0.19 256.64 1563 0 0 0 1.28 36 80 9 30 69.19 72 2 -0.97 256.88 1563 0 0 0 1.792 45 80 11 30 37.74 73 2 -0.19 257.18 1563 0 0 0 1.28 14 80 10 29 44.03 70 2 -7.78 257.42 1563 0 0 0 2.048 14 80 13 30 50.32 64 3 -9.93 257.71 1531 0 0.0195 0.039 1.792 21 80 21 29 94.35 63 2 -7.98 257.98 1594 0 0.039 0.0975 5.12 38 106 58 22 201.28 73 7 -0.78 258.28 1531 0 0.234 0.078 5.376 50 113 66 21 220.15 74 7 0.39 258.54 1563 0 0.078 0.8385 5.376 49 113 68 20 232.73 74 7 0.59 258.85 1563 0 0.8385 0.429 3.072 49 112 50 25 100.64 74 4 0.98 259.09 1531 0 0.0195 0 4.096 43 124 48 26 100.64 72 5 0.39 259.4 1563 0 0 0 1.536 14 136 13 29 44.03 69 2 -7.78 259.66 1531 0 0 0 1.024 13 80 8 29 31.45 54 1 -9.93 259.93 1563 0 0 0 1.024 13 100 0 5 0 50 1 -10.9 260.17 1563 0 0.0195 0.039 0 15 100 5 20 18.87 54 0 -10.9 260.47 1563 0 0.039 0.0195 0 24 100 8 19 25.16 61 0 -6.03 260.72 1531 0 0 0 0 30 100 9 19 31.45 62 0 -2.14 261.03 1656 0 0.0195 0.039 0 31 100 6 20 18.87 71 0 -1.16 261.26 1469 0 0 0 0 38 100 8 19 25.16 71 0 -0.78 261.57 1531 0 0 0 1.536 14 80 17 29 69.19 68 2 -7.2 261.8 1500 0 0 0 1.792 13 80 11 32 44.03 54 2 -9.73 262.1 1531 0 0 0.0195 1.28 13 80 8 29 37.74 54 2 -10.9 262.35 1500 0 0 0.0195 0 13 100 8 19 31.45 54 0 -11.09 262.64 1500 0 0 0 0 13 100 9 19 44.03 54 0 -10.9 262.88 1500 0 0 0 1.28 24 80 9 21 31.45 65 2 -6.42 263.15 1500 0 0 0 1.28 31 80 9 29 31.45 68 2 -1.75 263.37 1469 0 0 0 0 35 100 9 19 0 67 0 -0.97 263.67 1563 0 0 0.0195 0 38 100 33 28 106.93 71 0 -0.58 263.91 1531 0 0.0195 0.0195 4.608 36 109 46 25 88.06 70 6 -0.58 264.2 1469 0 0 0 2.304 14 118 23 29 75.48 67 3 -7.39 264.44 1469 0 0.0195 0.0195 2.304 13 125 17 29 50.32 54 3 -9.93 264.72 1469 0 0.078 0.6825 1.28 13 80 12 29 44.03 54 2 -10.9 264.97 1469 0 0.039 0.039 1.536 13 80 11 29 37.74 54 2 -11.09 265.26 1469 0 0.039 0.039 1.792 22 80 20 28 94.35 63 2 -7.98 265.51 1531 0 0.039 0.039 2.304 31 105 26 28 69.19 71 3 -1.55 265.77 1500 0 0 0 3.84 40 112 48 24 138.38 72 5 -0.58 266.01 1469 0 0.0195 0.0195 4.608 26 122 53 23 132.09 70 6 -2.53 266.31 1500 0 0.8775 0.8385 3.072 14 119 35 28 75.48 62 4 -7.78 266.56 1500 0 0.936 0.936 2.304 13 115 25 29 75.48 54 3 -9.93 ... 374.83 1438 0 0.0195 0.0195 3.072 15 116 32 28 81.77 70 4 -6.42 375.09 1438 0 0.039 0.0195 2.56 15 123 22 29 69.19 67 3 -8.95 375.33 1375 0 0.078 0.429 3.328 29 126 41 26 94.35 66 4 -3.11 375.64 1375 0 0.0585 0.0195 1.792 36 126 15 28 44.03 71 2 -0.78 375.89 1469 0 0 0 1.28 36 100 0 4 25.16 68 2 -0.97 376.2 1281 0 0.0195 0.0195 1.536 33 80 8 27 31.45 68 2 -0.97 376.46 1469 0 0 0 1.28 22 80 9 28 37.74 65 2 -4.47 376.76 1406 0 0 0 1.536 14 80 13 28 50.32 62 2 -8.76 377 1406 0 0 0 2.56 19 101 23 27 75.48 60 3 -8.17 377.3 1375 0 0.039 0.0585 3.328 25 109 41 26 106.93 64 4 -4.09 377.56 1375 0 0.7995 0.741 4.608 36 102 59 20 150.96 71 5 -0.78 377.87 1406 0 0.234 0.2535 4.864 36 111 63 20 163.54 71 6 -0.39 378.11 1406 0 0.7995 0.741 4.608 36 104 63 20 169.83 71 5 -0.39 378.4 1438 0 0.117 0.156 5.12 36 112 64 20 201.28 71 6 0 378.66 1469 0 0.624 0.819 4.864 36 109 65 20 207.57 71 6 0.2 378.97 1469 0 0.078 0.351 4.864 36 109 66 21 213.86 71 6 0.39 379.21 1500 0 0.7215 0.78 5.12 36 111 66 21 213.86 71 6 0.39 379.53 1531 0 0.2535 0.4485 5.12 36 107 67 21 220.15 71 7 0.59 379.79 1563 0 0.819 0.4485 5.632 42 112 70 20 239.02 73 7 1.37

Jim,

As I stated in my email to you, the 94's don't use a CAS. They have seperate cam and crank sensors. It could be the power transistor failing and cutting spark. If you lost RPM signal I would say crank sensor, but that doesn't seem to be the case.

I'll see you Monday!

What gear was this in?

Quote:

Originally Posted by PharmEcis

It could be the power transistor failing and cutting spark.

Sounds plausible considering the capacitor was not reconnected when the coil pack was replaced and it was run that way for a full year and thousands of miles.

Quote:

Originally Posted by rawavr4

What gear was this in?

It usually happens in a high gear when cruising. It has happened once at idle and once in second gear (which was not a fun experience).

any updates to this? Curious to the fix.

Yes, i thought I posted it. My ground wire pin in the coil pack connector(engine harness side) was damaged and i was getting an intermittent ground which is why it shut off at random times. I replaced the pin with one I had from another connector and problem solved.

Well thats my fix, I dont know if you were talking about the other guys problem.