bdmlilburn

http://www.autozone.com/autozone/rep...-1990%20Accord

http://www.autozone.com/autozone/rep...-1990%20Accord

i own a 90 accord ex 4 door manual. the above two links are vacuum tube diagrams. my main concern is the egr vacuum system since i am having trouble passing emissions. the first diagram shows the egr valve being connected to a hose coming out of the bottom of the control box(16). however on my car hose number (8) goes to the egr valve instead of (16). i attempted switching the hoses today but all it did was make my car/engine shake at idle. my hose number (8) currently has no vacuum due to a sri intake mod but i still have the sensor and the vacuum hoses plugged up. just purchases this car about two weeks ago and it was setup like this. dont seem right to me

if i was to guess i would say my egr ports are clogged and having it hooked up the right way is what was making my engine idle rough? or maybe there is some other fault in the egr system. looking for a professional opinion though

also i have heard that there are other intake manifolds that have threaded egr port plugs so that they can be removed without all the drilling and bs? is this true and if so which manifolds can i use from what cars/years?

holmesnmanny

The '91-'93 intake manifolds have egr plugs that you can drill and pull out. Only the '90 has no plugs. You can probably also just take it down to a machine shop and have it hot bathed as well.

The first thing you can try is just to pull the egr valve and clean inside it until the valve opens and closes freely. Make you u PB the nuts before you work on them. They can be a bitch to get off and they love getting rounded. The one in the back is especially tough.

phootbag

To check for clogged EGR ports, open the EGR valve at idle. I believe on that car due to the vacuum controlled valve you can actually lift up on the valve with your hand to open it.

If the car dies, the ports are clear. If the car stumbles a bit but not much, the ports are likely clogged. You can further diagnose which ports are clogged by opening the EGR valve at idle and disconnect the spark plug wires one at a time. The cylinders that react aren't getting exhaust gases and have plugged ports. The cylinders that don't react are getting exhaust gases and their respective ports are not clogged.

phootbag

Looking at that diagram, if 8 goes to your EGR valve, the hoses are hooked up wrong.

chikin pickle

If you switched the hoses, assuming you hooked them up correctly and you EGR turned on your solenoid is shot. It's leaking vacuum or getting a bunk signal and allowing you valve to lift when it shouldn't be.

That tells me, that some knucklehead just moved the hose to make it stop rather than solve the actual problem.

With the engine idleing hook up a vacuum guage to the number sixteen hose where it comes out of the black box. There should be no vacuum at idle. If you have some, then look into the EGR system more closely.

bdmlilburn

if the 90s dont have removable plugs then i think someone has already swapped a later manifold on because the 4 ports that have the egr holes underneath them all have concave plugs while the two closer to the engine still have the original plugs

bdmlilburn

at idle number 16 valve has some vacuum. i dont have a vacuum gauge but when i put my finger over the egr valve side of the hose i can feel some suction at idle.

guessing this means its one of the two:
constant vacuum control(cvc)-19
egr control solenoid valve-21

also i want to add i currently have no vacuum hose connected the egr solenoid and i am not throwing any codes. wiring diagram
http://www.autozone.com/autozone/rep...ngine%20wiring

gonna be checking the egr control solenoid valve wires
pink-grounded to ecm
blk/yel-12v with ignition on