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Hey everyone new member here, recently picked up a 1990 f150 with the 4.9L engine. Trying to clear up a code 44 and it looks like my combination bypass/diverter valve needs replacement. I'm having a hard time finding one and wondering what the story is on these? Are they not made anymore? Any chance of aftermarket parts? Been looking around online without much luck. Any help is appreciated, thank you in advance.
I'm learning, but not well versed on ford emissions. Will that work ok in place of the combination valve(s)?
I just looked up Summit since they are a good source and put in your truck and searched for the valves. I saw they carried them and just forwarded that picture to you. I assumed they carry the combination valve and looked no further since I was in a hurry.
Vjsimone is correct about the vacuum solenoids possibly being your issue. You would need to check the TAB and TAD solenoids for proper function. Also the Diverter can be checked for proper operation. There are several ways to check these components and I feel Vjsimone or another emissions proficient person can give you better help than me on this problem. These checks will hopefully help you avoid buying parts you don't need. Sandy
I do like not needing to buy parts, the TAB and TAD checked out according to Haynes procedure. EVR failed and was replaced. I've replaced all the vacuum lines with silicone. (At least one plastic line was partially melted, handful of rubber ones were cracked) I thought I had a good read on diverter/bypass valve but I'm not sure now, opened it up and found a small tear in diverter diaphragm, I've since glued it and put it back in, planning on going over the system again.
If the valves, vacuum lines, and solenoids check out, what else would/could cause the problem? I've read a few different things ranging from 02 sensors to egr solenoids to clogged catalytic converter.
I would think that the tear in the diaphragm would render the diverter non functional. If your glue works hopefully that will clear the code. You might also check and see if you can just buy the diaphragm part of the diverter. As I understand, you are just trying to clear code 44. Are you having other issues? Sandy
Also a salvage yard would be a good place to pick up another one,
It's only the code 44 right now. I live in California and need to get the truck smogged soon. I'm concerned the thermactor system not running right will keep me from passing. I like the idea of just replacing diaphragms.
Alright so I tested the bypass/diverter valve again, looks like a no go. I can get air to the converter line when applying vacuum to bypass valve but when i apply vacuum to both valves there's no air going to the exhaust manifold.
So it looks like I gotta find a replacement, pick n pull is an option but it's a couple hour drive and there's no garuntee. Does anyone here know if anything aftermarket is still an option? Found some crossover numbers for standard motor, airtex, wells but can't seem to find a place with any in stock.
Hey everyone new member here, recently picked up a 1990 f150 with the 4.9L engine. Trying to clear up a code 44 and it looks like my combination bypass/diverter valve needs replacement. I'm having a hard time finding one and wondering what the story is on these? Are they not made anymore? Any chance of aftermarket parts? Been looking around online without much luck. Any help is appreciated, thank you in advance.
There's an ID engineering number printed on this label (it's not 0E01B), post what it is.
