well idk ive swapped two motors in my truck one from an 89 and one from an 92 both into my 88, and i havnt had any problems with any of them
That would be because NEither your '88 or any of the LATER 2.9's had EGR.
ONLY the '86-87 2.9's had EGR.
You're all making my head spin, this is far more complicated than it needs to be.
What's wrong with just swapping the upper intakes and retaining the stock '87 exhaust? Would they honestly go through the hassle of verifying that the engine was in fact from a newer model, even though they're pretty much identical? What am I missing?
The upper intake isn't different, nor is the lower intake.(the '88-92's use a blank-off plate on the upper intake)
The reasons for the EGR to be there is unclear, because in an objective test the engine actually runs to (and exceeds) the emmissions standards at the time it was made without it.
And if you use the legal loophole I pointed out above it's one less part that can "Fall off", break or leak at an annoying time.
the '88-up Y-pipe is less likely to LEAK and exhaust leaks will fail you for emmissions every bit as quickly as any other cause.
I take particular offense over exhaust leaks BEFORE the catalyst(they tend to be noisier too)
In short, you DO NOT "need" the EGR to pass smog tests in ANY state, because it will pass a "sniff" test regardless, and a visual test can be bypassed by having retrofitted a later engine with all of THE LATER ENGINE'S emmissions components.(and if don't feel like doing this you can easily "simulate it" to a degree that would leave anyone besides me and mabey five or six other people in the country unable to tell exactly what you had done....
and of those five or six other people atleast four of them
are old-timers on these forums and the last one is Sven Pruitt.
Because to tell some things you'd literally have to disassemble
the engine and read casting numbers that are normally invisible
Sample questions:
Q: Where is the EGR?
This is an '88 (or '89 or '90 or '91 or '92) engine and they didn't have EGR.
Q: Why is the EGR port in the exhaust manifold plugged?
A:Because the later manifold was cracked and the casting
numbers were the same.
If one were using a California MAF 2.9 system you have to use the ENTIRE system....
Thankfully I've gotten away from all that.
I have a complete '93 4.0 explorer engine in my Ranger
now and have accumlated just shy of 2000miles on it
without a single engine operating system related problem.
AD