BigDav782 Posted September 19, 2019 Share Posted September 19, 2019 Going to start more-seriously troubleshooting my truck that recently decided it didn't want to start, and have read through chapter 5 of the EVTM a number of times. But I'm stuck on one detail that is perhaps silly: do all the checks on pages 32-34 apply to my truck that has EEC-IV? The headings appear to make it look like they only apply to trucks that are DS-II. Thanks! Dave Link to comment Share on other sites More sharing options...
Gary Lewis Posted September 19, 2019 Share Posted September 19, 2019 You did not say which of the three EVTM's (1981, 1985, or 1986) you are referencing, but I'm going to guess that it is the '86 as pages 32 - 34 seem to match your question. I've copied the first page here to make reference easier. See in the middle-top where it says Ignition-EEC IV and directly below that it says See Electronic Engine Control. You need to go to that section of the EVTM. Link to comment Share on other sites More sharing options...
BigDav782 Posted September 20, 2019 Author Share Posted September 20, 2019 You did not say which of the three EVTM's (1981, 1985, or 1986) you are referencing, but I'm going to guess that it is the '86 as pages 32 - 34 seem to match your question. I've copied the first page here to make reference easier. See in the middle-top where it says Ignition-EEC IV and directly below that it says See Electronic Engine Control. You need to go to that section of the EVTM. Thanks Gary. But there aren't any troubleshooting steps in the EEC section of the EVTM - so how am I to start diagnosing a no-spark condition? I've already disconnected the battery terminals in an attempt to check their condition, so I don't anticipate I can get any codes at this point. Link to comment Share on other sites More sharing options...
Gary Lewis Posted September 20, 2019 Share Posted September 20, 2019 Thanks Gary. But there aren't any troubleshooting steps in the EEC section of the EVTM - so how am I to start diagnosing a no-spark condition? I've already disconnected the battery terminals in an attempt to check their condition, so I don't anticipate I can get any codes at this point. The TFI ignition works very similarly to the DS-II ignition. There's a pickup module in the distributor, just like DS-II. The signal from it goes to the ECU instead of the DS-II module, and the ECU triggers the TFI coil that is very similar to the DS-II coil except it sits on the distributor instead of the engine. So I'd start by checking to see if you even have spark. Pull a plug wire and put an old plug in it and lay the plug against the engine. Crank the engine and watch for spark. I don't know if you have EEC-III or IV, but there's a very complex set of testing instructions for the IV here: http://www.garysgaragemahal.com/electronic-engine-control-eec.html. Perhaps they will help? Link to comment Share on other sites More sharing options...
BigDav782 Posted September 20, 2019 Author Share Posted September 20, 2019 The TFI ignition works very similarly to the DS-II ignition. There's a pickup module in the distributor, just like DS-II. The signal from it goes to the ECU instead of the DS-II module, and the ECU triggers the TFI coil that is very similar to the DS-II coil except it sits on the distributor instead of the engine. So I'd start by checking to see if you even have spark. Pull a plug wire and put an old plug in it and lay the plug against the engine. Crank the engine and watch for spark. I don't know if you have EEC-III or IV, but there's a very complex set of testing instructions for the IV here: http://www.garysgaragemahal.com/electronic-engine-control-eec.html. Perhaps they will help? Thanks Gary. EEC-IV, and I don't have spark at the plugs or at the distributor (used an inline spark tester in between several plugs, and then also in between coil and distributor). Truck was running OK until it all of a sudden died and won't start. Link to comment Share on other sites More sharing options...
Gary Lewis Posted September 20, 2019 Share Posted September 20, 2019 Thanks Gary. EEC-IV, and I don't have spark at the plugs or at the distributor (used an inline spark tester in between several plugs, and then also in between coil and distributor). Truck was running OK until it all of a sudden died and won't start. Then use that testing procedure as best you can w/o the fancy tools. Don't miss the PIP that gives crank info. Link to comment Share on other sites More sharing options...
Steve83 Posted September 20, 2019 Share Posted September 20, 2019 The signal from it goes to the...ICM on the base of the distributor - not to the EEC. The best diagnostic procedure for TFI-IV '85-93 is Haynes Ch.5 (usually Sec.5 or 7, depending on edition). https://supermotors.net/getfile/449785/thumbnail/hayneses.jpg Link to comment Share on other sites More sharing options...
BigDav782 Posted September 21, 2019 Author Share Posted September 21, 2019 The signal from it goes to the...ICM on the base of the distributor - not to the EEC. The best diagnostic procedure for TFI-IV '85-93 is Haynes Ch.5 (usually Sec.5 or 7, depending on edition). https://supermotors.net/getfile/449785/thumbnail/hayneses.jpg Went through this procedure and believe the PIP is bad, as you suspected Gary. Is that something that can be replaced on its own, or new distributor? If the latter, any tips? Link to comment Share on other sites More sharing options...
Steve83 Posted September 22, 2019 Share Posted September 22, 2019 Went through this procedure and believe the PIP is bad, as you suspected Gary. Is that something that can be replaced on its own, or new distributor? If the latter, any tips? Mark the distributor base to the block before loosening the clamp bolt, and mark the rotor to the bowl as the last gear tooth clears the cam gear. https://supermotors.net/getfile/1134330/thumbnail/diststabv8.jpg Link to comment Share on other sites More sharing options...
Gary Lewis Posted September 22, 2019 Share Posted September 22, 2019 Went through this procedure and believe the PIP is bad, as you suspected Gary. Is that something that can be replaced on its own, or new distributor? If the latter, any tips? Yes, the pickup in the dizzy can be replaced. But it may be almost as cheap, and much easier, to put a remanufactured distributor in. If you do the latter do as Steve said and mark the dizzy and block and then transfer the mark on the old dizzy to the new dizzy. And mark on the dizzy you take out where the rotor is pointing before you pull it. When you go back in with the dizzy you'll have to start several degrees CCW because as the dizzy goes down the angled gears mesh and rotate the rotor. And you want to end up with the rotor pointing right were it did and the distributor going back where the other one was, mark to mark. And the reason it is easier to go with a new/reman'd dizzy is that getting the pickup out can be fiddly. The reluctor, the gear-shaped wheel, has to come out and to get it out you have to pry up on it, gently, from two sides at the same time. And you don't want to break it. Plus, as you bring it up there's a roll pin that is in a slot to keep the reluctor located on the shaft, and it is easy to drop the roll pin in the dizzy. Once the reluctor is out the pickup can come out and the new one put in. Then put the reluctor back, with the roll pin in to locate it. Link to comment Share on other sites More sharing options...
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