2.9 swap

[bassman9114]

I need to swap 2.9's, the one i have has an egr on it the one i want to buy doesnt. can i do this, and what about the computer?-joe

[MAKG]

The COMPLETE emissions system has to stay with the engine for it to be legal. That includes the computer AND the exhaust.

An alternative is to swap long blocks.

[AllanD]

It is Legal to "update" to a newer year engine IF and only if ALL the emissions controls from that engine are swapped with it.

The interesting thing on 2.9's is that while the '86-87 2.9's have EGR the later 2.9's made from 1989-92 DO NOT.

You'll need the computer from the later engine (it plugs right in)
and you get the happy job of removing the EGR system.

The "thing" about EGR on the 2.9 is that the system is failure prone.
/Not so much the EGR valve itself, but the metal tube that feeds exhaust to the valve and especially the vacuum lines that the system is controlled with.

ANY sort of "failure" of the system and the relatively stupid management
decides that the situation is not good and runs the engine full rich.

The one "ugly" part that might be overlooked is that the '86-87's use a different Y-pipe and a different style mating flange to the catalytic converter.


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[rangernotlifted]

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

[Carlos Murphy]

As far as EGR systems go, this should pertain to all but I speak from experience with 70's BMW's, as a EGR filter begins to "clog" the engine will run better.

In some cases it will not pass smog but will still run better.

Carlos Murphy
Douglas County Nevada, no smog equipment required :icon_cheers:

[Ranger Stranger]

I have an 87 ranger with a dieing 2.9 motor. A local guy has a 2.9 out of a 90 ranger. He does not have the computer available, so how much will I have to swap to make the 90 engine work with my 87 computer? I know the blocks are the same, but aren't there some differences in the heads?

Thanks,

Tim

[rusty ol ranger]

The heads are stronger on 88 and later ones.

I dont see why you would have to swap computers, unless your 87 Computer will be looking for input from the EGR which wont be there.

Worse case scenario just go to the junkyard and get a computer from a Non EGR 2.9L, it should be the same.

Or find a 86-87 2.9L, which according to some people run harder then the later ones.

later,
Dustin

[Psychopete]

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?

I have an '88 PCM from a MAP/SD 2wd 2.9L A4LD Ranger that I need to get rid of. It worked fine when pulled, MAF conversion is the reason it's no longer in use. If you don't have a lot of time, or hate wiring diagrams, you might hesitate to swap PCMs. I would be reluctant to just blindly put it in and trust an assumption that it's "supposed" to work.

There were slight differences in the wiring from my 88 to 90 Cali., and that's just not the addition of the mass air flow sensor. It wasn't bad actually, I'd rather do that than a 87 -> 88.

Pete

mikhail:
'88s were not equipped with EGR unless it was swapped in by someone else. There's an error above.

[MAKG]

As I said, an alternative is to swap long blocks.

It really is the simplest way.

The lower intakes MIGHT be identical -- and I think they are for 2.9Ls. Make sure the manifold-mounted sensors (CTS and gauge sender) are identical and of course put in a new thermostat.

That way, it's still an '86-'87. JUST removing the EGR may create performance issues because you can have a more aggressive timing curve with EGR than without. And it really is illegal -- and very obvious to any inspector, as well as very expensive -- to disable it.

[AllanD]

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.

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