Can a bad EGR valve prevent the engine from starting? (8 Viewers)

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e9999

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I suspect that I may have some issues with my EGR given an OBD code I saw before. Is it possible that it might prevent the engine from starting at all (cranking but not firing) as I'm experiencing now? Perhaps by being stuck in the wrong position?
I'm thinking that may be possible since you can kill the engine (when running already) by manipulating the EGR as is done during a smog test for instance, although admittedly that is a different situation as there are no exhaust gases to recirculate with the engine not firing. But maybe that messes up the AFR?
What would be a good way to tell if it does that, short of replacing it?
TIA
 
I suspect that I may have some issues with my EGR given an OBD code I saw before. Is it possible that it might prevent the engine from starting at all (cranking but not firing) as I'm experiencing now? Perhaps by being stuck in the wrong position?
I'm thinking that may be possible since you can kill the engine (when running already) by manipulating the EGR as is done during a smog test for instance, although admittedly that is a different situation as there are no exhaust gases to recirculate with the engine not firing. But maybe that messes up the AFR?
What would be a good way to tell if it does that, short of replacing it?
TIA

If the EGR valve is open, that'd mean that exh gas from #6 is going into the intake. Would this be considered "pirate air"? I wouldn't think it'd prevent the engine from actually starting though. If the AFR is jacked, that still wouldn't prevent it from starting, may not idle smoothly however! If you confirmed spark and fuel (46psi at the rail) then something else is amiss. Even a massive vac leak may not cause a no start condition but idle would be erratic along with a loud hissing sound.
 
Back to the basics. With the key in the run position, before turning to the start position, is the check engine light illuminated? If not then the ECM is not being powered and will never start. If you messed with the battery could have damaged the fusible links.
 
^^^ Yes, I still need to verify that there is fuel getting to the injectors. To be done soon.
^^ Yes, I can test the EGR but I'd rather not do that now unless I know that it's a potential culprit. Last time I checked it, it worked fine IIRC, but it has been sitting a while since then.
^ Yes, the MIL comes on before I start cranking, then goes away while cranking, and then shows again after I stop cranking. Don't know if the latter means anything as I do not see any OBD code so far.

TBH, I could be fairly easily convinced that it's unlikely that the EGR would completely prevent starting. I suppose my not so friendly relationship with the blasted thing made me think the worst of it right away...

Thanks!
 
^^^ Yes, I still need to verify that there is fuel getting to the injectors. To be done soon.
^^ Yes, I can test the EGR but I'd rather not do that now unless I know that it's a potential culprit. Last time I checked it, it worked fine IIRC, but it has been sitting a while since then.
^ Yes, the MIL comes on before I start cranking, then goes away while cranking, and then shows again after I stop cranking. Don't know if the latter means anything as I do not see any OBD code so far.

TBH, I could be fairly easily convinced that it's unlikely that the EGR would completely prevent starting. I suppose my not so friendly relationship with the blasted thing made me think the worst of it right away...

Thanks!
When I started the rehab of our ‘94 most elements of the EGR were shot. Pointless shaft was stuck, VSV leaked and carbon was caked in the IM. None of this prevented the car from running well.
 
^ good to know, thanks! Although I suppose one could argue it may depend on how it's stuck, but that is the devil's advocate talking, I guess.
 
^^^ Yes, I still need to verify that there is fuel getting to the injectors. To be done soon.
^^ Yes, I can test the EGR but I'd rather not do that now unless I know that it's a potential culprit. Last time I checked it, it worked fine IIRC, but it has been sitting a while since then.
^ Yes, the MIL comes on before I start cranking, then goes away while cranking, and then shows again after I stop cranking. Don't know if the latter means anything as I do not see any OBD code so far.

TBH, I could be fairly easily convinced that it's unlikely that the EGR would completely prevent starting. I suppose my not so friendly relationship with the blasted thing made me think the worst of it right away...

Thanks!
I don’t think your EGR valve would prevent the 80 from starting. I would remove the fuel pump assembly to inspect condition and the fuel pump soft line and sock for damage/clogging. I have seen that rubber fuel line from the pump to the hardline split if it’s been sitting in bad gas for an extended period of time which will degrade the rubber. If it splits, you’re losing most of your fuel pressure from the pump to the injectors. Also, once you take the assembly out, you can see if you have rust buildup around the sock which would indicate more issues upstream as in clogged filter and injectors.
 
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