Runs badly
- Thread starter jusssi
- Start date
RealFastV6
@jb_and_his_coffee
IGottaSy
Active member
Re: Runs badly
No Mention Of Before CHANGING parts. I storage? Just doing maintenance ? Bought as is?
No Mention Of Before CHANGING parts. I storage? Just doing maintenance ? Bought as is?
Jimmy
Banned
Davemc1963
93 Ty Owner
Re: Runs badly
Looking at the vid, the tach dosen't look to be following the actual engine speed (reading low) as well as the fluttering as has already been mentioned.
Bad grounds spring to mind for fluttering tach, but theres more going on here.
I suspect that there could be an issue with the tune/eprom - try removing and reseating the eprom, or substituting eprom for another if you can borrow/buy one.
When it goes closed loop, try shorting out the temp sensor connector by the thermostat housing to fool the ecu that the engine is hot, just to rule that out, but I dont think that would be the only problem here.
Although doubtful, because you would have a warning light on and a code set (you have checked for/read the trouble codes again?) Is the EST wire connected under the dash? and is the timing correct? - you need to confirm the balancer outer ring hasn't slipped (very common with the stock dampener - not an if, more 'a when') and that you have true tdc when the timing mark shows zero before you start.
Two last things.
Very old/bad gas will let the engine start and run, but usually runs like crap, when you put a load on the engine. (this dosen't explain the low reading tach though). Also, you dont have any aftermarket ignition boxes or anything like that on there (or anything else non stock) that you haven't mentioned?
Looking at the vid, the tach dosen't look to be following the actual engine speed (reading low) as well as the fluttering as has already been mentioned.
Bad grounds spring to mind for fluttering tach, but theres more going on here.
I suspect that there could be an issue with the tune/eprom - try removing and reseating the eprom, or substituting eprom for another if you can borrow/buy one.
When it goes closed loop, try shorting out the temp sensor connector by the thermostat housing to fool the ecu that the engine is hot, just to rule that out, but I dont think that would be the only problem here.
Although doubtful, because you would have a warning light on and a code set (you have checked for/read the trouble codes again?) Is the EST wire connected under the dash? and is the timing correct? - you need to confirm the balancer outer ring hasn't slipped (very common with the stock dampener - not an if, more 'a when') and that you have true tdc when the timing mark shows zero before you start.
Two last things.
Very old/bad gas will let the engine start and run, but usually runs like crap, when you put a load on the engine. (this dosen't explain the low reading tach though). Also, you dont have any aftermarket ignition boxes or anything like that on there (or anything else non stock) that you haven't mentioned?
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jusssi
Member
Re: Runs badly
Thaks for responses. Engine internals are ok. I pulled distributer check'd pickup coil and turned dist better position so wires are better routed now. Timing set to 0. All stock with ignition system. Found fuel pump voltage loss about 2 volts. Made kinda hotwire system and pump runs much better, but no effect to bad running engine.
Typical situation: Start engine, it sets on idle and closed loop, misfiring and slightly pos at exhaust about every couple seconds, ilde speed not steady, when rev to 2000rpm may run very well, no popping and misses, wbo2 keeps steady on 1 , but suddenly start misfire and stumble very badly and dies if lift gas pedal.
Thaks for responses. Engine internals are ok. I pulled distributer check'd pickup coil and turned dist better position so wires are better routed now. Timing set to 0. All stock with ignition system. Found fuel pump voltage loss about 2 volts. Made kinda hotwire system and pump runs much better, but no effect to bad running engine.
Typical situation: Start engine, it sets on idle and closed loop, misfiring and slightly pos at exhaust about every couple seconds, ilde speed not steady, when rev to 2000rpm may run very well, no popping and misses, wbo2 keeps steady on 1 , but suddenly start misfire and stumble very badly and dies if lift gas pedal.
Jimmy
Banned
Re: Runs badly
Overstating the obvious,but have you verified that the plug wires are in the right places on the dist cap? Sometimes they aren't. :dunno:
One time I did a tuneup on Joe's Aspen Blue,then it wouldnt start. Had every wire 1 place off on the dist,fixed it and boom.Then Joe boost launched it in front of a cop that ignored us.When Christina drove it WOT for 50' and let off of it and said "It never did that before" I knew it was all good.
Overstating the obvious,but have you verified that the plug wires are in the right places on the dist cap? Sometimes they aren't. :dunno:
One time I did a tuneup on Joe's Aspen Blue,then it wouldnt start. Had every wire 1 place off on the dist,fixed it and boom.Then Joe boost launched it in front of a cop that ignored us.When Christina drove it WOT for 50' and let off of it and said "It never did that before" I knew it was all good.
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Davemc1963
93 Ty Owner
Re: Runs badly
Assuming you have a stock dampener. Have you confirmed '0' on timing tab to dampener outer ring (using the second dampener line) is actually true tdc on cyl1?
Might sound like a stupid question, but can you confirm you set the timing with the EST wire disconnected and at or around normal idle speed?
Out of interest, how did it run with the EST wire disconnected?
Assuming you have a stock dampener. Have you confirmed '0' on timing tab to dampener outer ring (using the second dampener line) is actually true tdc on cyl1?
Might sound like a stupid question, but can you confirm you set the timing with the EST wire disconnected and at or around normal idle speed?
Out of interest, how did it run with the EST wire disconnected?
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jusssi
Member
Re: Runs badly
Ok, there's no stupid questions, appreciate all help I get
I check'd wires, ok, new dampener, and set ign timing est wire disconnected and also then start misfire etc. One notice is that when engine runs and I have tunerpro connected and when it start to stumble and misfire bad same time appears connect errors in tunerpro. That makes me wonder if there's ecm problem..?
Ok, there's no stupid questions, appreciate all help I get
I check'd wires, ok, new dampener, and set ign timing est wire disconnected and also then start misfire etc. One notice is that when engine runs and I have tunerpro connected and when it start to stumble and misfire bad same time appears connect errors in tunerpro. That makes me wonder if there's ecm problem..?
anryo
Donating Member
Re: Runs badly
All of this is very good information, because my truck does exactly the same. It is not that bad, although, but the tach is jumping similarily and it misfires every 3-5sec.
BTW - how to check TDC at home?
Jussi - were in the Finland are you living?
Edit:
I got it fixed! Yeah! In my case it was just incorrect timing and after setting it again, it runs like a charm. Sad, it does not help you much, as you have checked yours...
All of this is very good information, because my truck does exactly the same. It is not that bad, although, but the tach is jumping similarily and it misfires every 3-5sec.
BTW - how to check TDC at home?
Jussi - were in the Finland are you living?
Edit:
I got it fixed! Yeah! In my case it was just incorrect timing and after setting it again, it runs like a charm. Sad, it does not help you much, as you have checked yours...
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jusssi
Member
Re: Runs badly
Hey good for you anryo. :tup: I'm living in middle of finland about 350km from helsinki.
yesterday I checked plugs and nothing unusual there gapped 'em to 0.8mm.
Maybe it's best to bury this back to garage and start to repair my '65 volkswagen, it's probably easier...
Hey good for you anryo. :tup: I'm living in middle of finland about 350km from helsinki.
yesterday I checked plugs and nothing unusual there gapped 'em to 0.8mm.
Maybe it's best to bury this back to garage and start to repair my '65 volkswagen, it's probably easier...
anryo
Donating Member
Re: Runs badly
But reagrding the truck you have threeoptions for your problems:
- problems with fuel (pressure, pump, injector, filter)
- ignition (distributor, plugs/wires, ICM) or low current / bad grounding overall
- mechanical (compression, valves, vacuum leaks) or etc
BTW, I put extra wires from alternator to "+" and from alternator to ground/engine - the voltage was raised ~0.5V everywhere. From the factory, the grounding is insufficient in my eyes. Worth trying at least?
Heh... This is not "in the middle" of Finland...
But reagrding the truck you have threeoptions for your problems:
- problems with fuel (pressure, pump, injector, filter)
- ignition (distributor, plugs/wires, ICM) or low current / bad grounding overall
- mechanical (compression, valves, vacuum leaks) or etc
BTW, I put extra wires from alternator to "+" and from alternator to ground/engine - the voltage was raised ~0.5V everywhere. From the factory, the grounding is insufficient in my eyes. Worth trying at least?
