Code 71......Now what? (1 Viewer)

[GeoRoss]

Thanks Beo,
I was going through the FSM on Sunday night and was going through the VSV test. In calling for the removal of the air intake I realized why so many folks avoid testing it. I am collecting an order of Dan and was looking for any gaskets I would need just for the testing. I am glad I don't need to remove the air intake though. The only thing that I need to get is a vacuum gauge.

A few questions ...

When you say 'intake cleaner' do you mean something like carb cleaner? Does it really matter?

In my '94 FSM on EG-186:

STEP 3. INSPECT SEATING OF EGR VALVE
Start the engine and check that the engine starts and runs at idle.

QUESTION: This is after putting on the vacuum guage, does checking the EGR valve seating mean that it is in place correctly, clean, not stuck?

STEP 5. INSPECT OPERATION OF VSV AND EGR VACUUM MODULATOR WITH HOT ENGINE

c. Disconnect the vacuum hose port R of the EGR vacuum modulator and connect port R directly to the intake manifold with another hose.

QUESTION: Do you do the hose rerouting while the engine is running?

STEP 7. INSPECT EGR VALVE
a. Apply vacuum directly to the EGR valve with the engine idling.
b. Check that the engine runs rough or dies.

QUESTION: How do you apply the vacuum?

In my '94 FSM on EG-188:
EGR VACUUM MODULATOR INSPECTION

after testing for air passing through the filter with the engine off ...
d. Start the engine and maintain speed at 2500 RPM

QUESTION: Start the engine with all the vacuum hoses disconnected?

Thanks for the help

Ross

 

[Vitesse_6]

Jimbo and others with the 71 and/or P0401...

Read This thread in the FAQ. It covers the theory and testing of the individual components in the EGR system. Despite the protests of some, the proper repair of the EGR system is quite easy once you understand how it operates.

Post back if you have questions. Many, many guys on this forum have successfully fixed their EGR problems and will be willing to assist.

-B-

I just read this link in FAQ, Go figure I still have a green capped modulator...If I need to replace it, I will tear it apart and have a look.
Thanks again for all the great info!

EDIT
By tearing into the modulator, Do any of you konw if this will ruin it? I didnt want to ruin it till I got home if it would, Any thought's?

 

[Vitesse_6]

Update, I replaced the EGR Vac. Modulator today and have not had a CEL...Yet, I replaced it at the dealer and hopped on the I-15 South, Got off the freeway shut it down and drove another 8 miles or so without any issues, Figuring I would give it the 2 tries that I belive Beowolf or IdahoDoug mentioned*......?
When I got home I tried my hand at cleaning the EGR temp sensor, It was a pain in the butt however I got it off and cleaned it of all the carbon. I managed to ruin a 14MM wrenck in the prosess...lets say I surpassed its flexing strength
On a side note, I never saw that anyone had mentioned what the cost of doing the EGR temp sensor, Vac. Modulator, VSV, other like items, But it could run you in the $50-350.00 range depending on where and what you purchase, The reason I say this is money is an issue and I dont NEED to drive the 80 and I like to know what I may be up against.
So far so good
Have fun





* Sorry I dont remember due to all the reading Ive been doing of late

 

[Rusty Shackleford]

I had the 71 code. Replaced the EGR with new from cdan and it was fine till yesterday. The light came back on. I guess next is the modulator replacement. I can't stand the engine light staying on. So far this EGR problem is my only complaint on my new to me 80.

 

[Beowulf]

Rusty and Brian,
I can't tell you how many times that I have repeated this but you really, really need to do the tests in the FSM to isolate the EGR problem rather than buying EGR valves and EGR modulators and EGR temp sensors and vacuum valves. BTDT. Dan will love you; your wife will hate you. Your choice.

-B-

 

[drsales]

Mine was the ERG and Vac Valve.....plus a cup full of carbon. Nature of the beast I guess. Had the local handy dandy Toyota independent fix up guy do it. Ouch!

 

[Vitesse_6]

Rusty and Brian,
I can't tell you how many times that I have repeated this but you really, really need to do the tests in the FSM to isolate the EGR problem rather than buying EGR valves and EGR modulators and EGR temp sensors and vacuum valves. BTDT. Dan will love you; your wife will hate you. Your choice.

-B-

Thanks for your concern Beowolf, But I did a EGR check by removing and pluging the PS of the ERG and sucking on the other end, getting the engine to stall to some degree, and I did get quite a bit of carbon out of the Modulator, I asked if taking it apart would ruin it but I got no response.... Little did I Know there was a small filter in the top, I just didnt want to ruin it at work and not be able to drive it home.
In another post someone mentioned "if" you have a green top Modulator it should be replaced, Which I had and I did.
Im sure C-Dan would be more than willing to sell me parts at great prices, We have a club sponsor that sells us parts for nearly cost, I did happen to but the cheapest part on the list of items that could be the issue, At ~ $50 I couldnt pass it up considering a few other things ran in the $125+ range.
Please dont take this as a slap in the face, I know alot of the older more qualified members deal with this stuff all the time, I read through about 10 different looooooooong threads about what it might be, I figured things out and took action.
Thanks again for your help!

 

[Beowulf]

In another post someone mentioned "if" you have a green top Modulator it should be replaced, Which I had and I did.

You may have taken their comment a little too literally. I'm not sure who posted that but the qualifier would have to be if you have a non-working green top EGR modulator.

Kinda the same with the black fan clutches being replaced with the blue ones. No need unless your black one is failing or, if you're like me, and just wanted to replace the black one while you were doing a cooling system overhaul and to have a working trail spare.

-B-

 

[Vitesse_6]

Kinda the same with the black fan clutches being replaced with the blue ones. No need unless your black one is failing or, if you're like me, and just wanted to replace the black one while you were doing a cooling system overhaul and to have a working trail spare.

-B-

CRAP!

Now I need to go check
Thanks again

 

[Rusty Shackleford]

Thanks for your concern Beowolf, But I did a EGR check by removing and pluging the PS of the ERG and sucking on the other end, getting the engine to stall to some degree, and I did get quite a bit of carbon out of the Modulator, I asked if taking it apart would ruin it but I got no response.... Little did I Know there was a small filter in the top, I just didnt want to ruin it at work and not be able to drive it home.
In another post someone mentioned "if" you have a green top Modulator it should be replaced, Which I had and I did.
Im sure C-Dan would be more than willing to sell me parts at great prices, We have a club sponsor that sells us parts for nearly cost, I did happen to but the cheapest part on the list of items that could be the issue, At ~ $50 I couldnt pass it up considering a few other things ran in the $125+ range.
]

I did the same on my rig, and the light still shines. I'll have to check everything again and see if I can isolate the bad part again. At this point, my next solution is black tape.