NCReatta Posted January 23, 2012 Share Posted January 23, 2012 Ok, '90 Reatta coupe. Driving at 70 on the highway, and it just cuts off. Like someone just unplugged it. Pop the car into noNeutral , and it starts right back up. No problem.Recently replaced the MAF, and the IAC. Replaced both with cleaned used parts.Showing cam sensor as a history code.Thoughts? Link to comment Share on other sites More sharing options...
padgett Posted January 23, 2012 Share Posted January 23, 2012 (edited) Start switch. Did the radio continue to play & dash go blank ?When you restarted it you moved the switch contacts. Edited January 23, 2012 by padgett (see edit history) Link to comment Share on other sites More sharing options...
Ronnie Posted January 23, 2012 Share Posted January 23, 2012 Classic signs of a failing Crank Position Sensor or ICM. There is a slight possibility the oil pressure sensor is bad causing the fuel pump to shut down. I don't think the cam sensor will shut down the engine. Link to comment Share on other sites More sharing options...
Barney Eaton Posted January 23, 2012 Share Posted January 23, 2012 Since you have a building full of extra parts, why not try a different ECM. You can unplug yours and just lay the "trial" one on the floor. If nothing else, you eliminate the ECM and its connections as the problem. What bothers me is the restart without any time laps. Something is loosing contact and if it were, say at the ignition module, the car would stumble but continue to run. Your problem is someplace that when the circuit opens, reconnecting it does not allow the engine to run without resetting the start process. Link to comment Share on other sites More sharing options...
NCReatta Posted January 23, 2012 Author Share Posted January 23, 2012 Classic signs of a failing Crank Position Sensor or ICM. There is a slight possibility the oil pressure sensor is bad causing the fuel pump to shut down. I don't think the cam sensor will shut down the engine.Doubt it's the oil pressure sensor. ICM is a possibility, but it runs as smith as can be. I believe that may have been replaced. I'm leaning towards the cranks sensor. It just seems odd that it'll just cut off without warning, the. Immediately start right back up..Padgett, why would you say start switch? I've bypassed the resistor on this car, by the way. Link to comment Share on other sites More sharing options...
NCReatta Posted January 23, 2012 Author Share Posted January 23, 2012 Since you have a building full of extra parts, why not try a different ECM. You can unplug yours and just lay the "trial" one on the floor. If nothing else, you eliminate the ECM and its connections as the problem.What bothers me is the restart without any time laps. Something is loosing contact and if it were, say at the ignition module, the car would stumble but continue to run. Your problem is someplace that when the circuit opens, reconnecting it does not allow the engine to run without resetting the start process.That was my thought exactly. I'll be trying an ECM in a week or so. Agreed. The lack if time lapse is strange. No stumble, nothing. It just stops. It's really sporadic too. It'll work fine for a week or so, then it'll just cut off. Then it won't do it for a while. Link to comment Share on other sites More sharing options...
padgett Posted January 23, 2012 Share Posted January 23, 2012 Exactly, sudden cut off is electrical, instant heal is mechanical, why I asked if the dash went blank when it happened. Link to comment Share on other sites More sharing options...
Guest Rockin Reatta Posted January 23, 2012 Share Posted January 23, 2012 I had about the same thing happpening on my 90 coupe. It ended up being a bad fuseable link near the battery, the one that feeds the ecm. Link to comment Share on other sites More sharing options...
Larry Schramm Posted January 23, 2012 Share Posted January 23, 2012 Now I am not encouraging you to do this, but I have on occasion tapped the crank sensor with the engine running using a long rod or screw driver. If the car cust out then it is the crank sensor. You can also with the palm of your hand tap on the ecm and if it cuts out that would be a place to go. Just my thoughts. Link to comment Share on other sites More sharing options...
Guest Mc_Reatta Posted January 23, 2012 Share Posted January 23, 2012 I'd have to weigh in on the side of an electrical contact problem.If the ICM or CPS fail while running it's typically from a internal thermal problem and a restart would not be possible until it has cooled down enough to function again.Ignition switch is a possibility. Two telltale signs would be the blacking out of the IPC and the radio still functioning under RAP power as Padgett said. I would expect the switch would give some mechanical indications too as feeling sloppy when turned or needing a few turns or wiggling to get the car to start indicating wear of the pawl or actuator rod in the column. If you don't feel that's your problem then a power issue to the ECM is likely. When's the last time you checked and cleaned the power and grounding posts by the battery and on the engine under the hood?ECM failure is a possibility if there's a cracked solder joint internally, but would expect problem to be related to shocks and vibration stimuli, not when cruising down the interstate. Rapping on it while underway should quickly reveal if that's your problem. Would also expect at least some trouble codes to be set too. Link to comment Share on other sites More sharing options...
NCReatta Posted January 23, 2012 Author Share Posted January 23, 2012 Dash stated lit up. IPC radio lights and everything still worked. It was sort of damp last time it happened. Could a fuse able link be intermittent like this?Grounds haven't been checked or cleaned.No trouble codes. Ignition switch works just fine. Link to comment Share on other sites More sharing options...
Guest Recian Posted January 24, 2012 Share Posted January 24, 2012 Well like you said i'd check your grounds first, especially body ground. If your body ground is bad then the car tries to ground through the engine and could eventually cause issues until it overloads and goes away at restart. Increase with humidity leads me to believe there's a corroded connection somewhere. Check your ignition module and crank sensor connectors for corrosion. Also check the ignition module's connector rubber insulator. I had an issue with stumble and stalling with that awhile back on mine. Also check the connector for the injector harness. Mine had a broken wire at the connector when i got the car. Repaired that wire and had no problem starting it. It corroded from the inside out so make sure you dont see signs of corrosion. Then again the fact that it starts right back up makes it seem like a failure in a components circuit and when you restart it it jump starts that circuit and re-starts the car. Does it ever not restart? Link to comment Share on other sites More sharing options...
Ronnie Posted January 24, 2012 Share Posted January 24, 2012 Your problem is someplace that when the circuit opens, reconnecting it does not allow the engine to run without resetting the start process.That was what lead me to mention the oil pressure sensor as a possibility. If the contacts in the sensor that powers the fuel pump open momentarily you loose fuel pressure, engine dies, oil pressure zeros, contacts that power the pump open. Then when you turn the key off and back on, the ECM runs the fuel pump for a few seconds to prime the system and the engine restarts.Just a guess and kind of far fetched but it is possible. Link to comment Share on other sites More sharing options...
Guest Recian Posted January 24, 2012 Share Posted January 24, 2012 it's possible but if a fuel pump goes out you'll get a stumble as the remaining fuel psi in the lines dwindles down to 0. He said it dies out wiht no warning and under those conditions it wont start right back up cuz youll have to rebuild fuel PSI Link to comment Share on other sites More sharing options...
Jim Posted January 24, 2012 Share Posted January 24, 2012 (edited) From my experience I have seen several times when this happens it is a bad battery or ground cable where it attaches to the battery.Inside the large red and black rubber pieces the cables are crimped together and these crimps go bad. You cannot see the problem unfortunately.About the only solution if it is the battery or ground cable is to replace them. A person could cut away the red or black insulation and then recrimp the cables but even if this does solve the problem you will have to replace the cable if you want it to look like the factory cable.I do have good cables available. '88 cables were a little different from the '89-91s. Edited January 24, 2012 by Jim (see edit history) Link to comment Share on other sites More sharing options...
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