1987 Honda Prelude losing power once warm

> Hi,
> Intake. You can hook up vacuum gauge.

Thanks for the response!

Wouldn't that problem be evident even when the car is cold? Any links
or advice on how to test or where to buy a vacuum gauge?
 >> Stay informed about: 1987 Honda Prelude losing power once warm 

> Hi,
> Heat/cold expand/shrink things. You already done quite a few rmedial
> tries. Checking vacuum for proper level won't hurt.
> Also checking all the ground point like fuel pump ground joint is good idea.

OK I'll buy the heat expansion/contraction, but I'm also wondering if
that will solve the car complaining about the EGR problem (code 12 on
the ECU).

Most importantly, HOW do I check for a vacuum level on the intake
manifold? Got any links or suggestions?
 >> Stay informed about: 1987 Honda Prelude losing power once warm 

zardozrocks wrote:

> I have a 1987 Honda Prelude 2.0 SI. It's the fuel-injected model. If
> the car is cold, it will start up immediately and runs great - i can
> lay a patch of rubber. It will run perfectly immediately following a
> cold start. Once the car has traveled a few miles, however it starts
> to lose power quite dramatically as I attempt to rev it up past about
> 2000 RPM as though it were starving for fuel or air or something. The
> problem will happen in any gear but seems a teeny bit more pronounced
> in the higher gears. Around this time, the PGM-FI light comes on on
> the dash.
>
> I've been looking at this problem for some time now and I have had
> some repairs done:
> * rebuilt/replaced fuel injectors
> * new fuel pump
> * new air/fuel/oil filters
> * replaced EGR valve
> * checked main relay for broken solder - it seems fine
>
> After posting here previously someone told me to check the ECU codes.
> The ECU code that is blinking is code #12 which for my car means a
> problem with the EGR system. When I took the car in for repairs last
> January to a small shop, the mechanic claims he replaced the EGR valve
> so I'm inclined to rule that out.
>
> Any hints on what it could be? Would a clogged oxygen sensor result
> in the ECU sending code 12? Any advice would be much appreciated! I
> MUST fix this problem and simply cannot afford expensive repairs.
>
Hi,
Manifold vaqcuum leak?
 >> Stay informed about: 1987 Honda Prelude losing power once warm 

zardozrocks wrote:
>>Hi,
>>Manifold vaqcuum leak?
>
>
> Which manifold? How does one test it? Also, sounds expensive.
Hi,
Intake. You can hook up vacuum gauge.
 >> Stay informed about: 1987 Honda Prelude losing power once warm 

zardozrocks wrote:
>>Hi,
>>Intake. You can hook up vacuum gauge.
>
>
> Thanks for the response!
>
> Wouldn't that problem be evident even when the car is cold? Any links
> or advice on how to test or where to buy a vacuum gauge?
Hi,
Heat/cold expand/shrink things. You already done quite a few rmedial
tries. Checking vacuum for proper level won't hurt.
Also checking all the ground point like fuel pump ground joint is good idea.
 >> Stay informed about: 1987 Honda Prelude losing power once warm 

zardozrocks wrote:

> I have a 1987 Honda Prelude 2.0 SI. It's the fuel-injected model. If
> the car is cold, it will start up immediately and runs great - i can
> lay a patch of rubber. It will run perfectly immediately following a
> cold start. Once the car has traveled a few miles, however it starts
> to lose power quite dramatically as I attempt to rev it up past about
> 2000 RPM as though it were starving for fuel or air or something. The
> problem will happen in any gear but seems a teeny bit more pronounced
> in the higher gears. Around this time, the PGM-FI light comes on on
> the dash.
>
> I've been looking at this problem for some time now and I have had
> some repairs done:
> * rebuilt/replaced fuel injectors
> * new fuel pump
> * new air/fuel/oil filters
> * replaced EGR valve
> * checked main relay for broken solder - it seems fine
>
> After posting here previously someone told me to check the ECU codes.
> The ECU code that is blinking is code #12 which for my car means a
> problem with the EGR system. When I took the car in for repairs last
> January to a small shop, the mechanic claims he replaced the EGR valve
> so I'm inclined to rule that out.
>
> Any hints on what it could be? Would a clogged oxygen sensor result
> in the ECU sending code 12? Any advice would be much appreciated! I
> MUST fix this problem and simply cannot afford expensive repairs.
It looks more like a clogging fuel filter...
 >> Stay informed about: 1987 Honda Prelude losing power once warm 

Admittedly one does not want to replace things willy-nilly
at this point. And you say the Code 12 continues. (I also
confirmed Code 12 is symptomatic of a "problem" with the EGR
system.) Using the manuals at the sites below, I would be
checking the EGR's electrical connections first. Yes, it's
new, so this suggests that, if it's not working, it's more
likely that the connections were not made correctly.

For troubleshooting codes yada for your Prelude:
http://www.autozone.com/az/cds/en_us/0900823d/80/0c/fb/59/0900823d800c...9/repai

Your Prelude's factory service manual:
http://www.honda.co.uk/car/owner/workshop.html

Next I would do what Motsco said. One must take seriously
purging air from the coolant system. If any repairs you had
done recently involved the coolant system in any way, I'd do
a purge, per the manual. It may take 50 minutes or so for
your car to warm up during the purge, so be patient. The
level appearing to be fine is not enough to indicate air is
fully purged.

If this Prelude is on its original, OEM oxygen sensor,
nonetheless I would consider replacing it. Your symptoms do
suggest a failing O2 sensor. Particularly the symptom that
it starts going amiss after warmup. If it is the original O2
sensor, then it is in fact quite old. A code will not
necessarily be thrown for its malfunction. You can get an
OEM O2 sensor from www.automedicsupply.com for under $40
total (= about $32 + shipping). In 2004, I used this online
store for a new O2 sensor for my 91 Civic (the Denso one).
Great service. No problems with the new O2 sensor.

Based only on reading here and a bit of googling, I'd also
investigate whether the catalytic converter was partly
plugged. Google on same for more info. Of course, then the
big question is how it got plugged. Related to the EGR
system?

Keep checking back. Others with more expertise will post.

Elle
Original owner and now sole mantainer, 1991 Civic
 >> Stay informed about: 1987 Honda Prelude losing power once warm 

P.S. for the record, when were ignition wires and plugs last
replaced and timing checked? Distributor cap and rotor? Were
OEM parts used?

It's amazing sometimes how often it's just old ignition
parts.
 >> Stay informed about: 1987 Honda Prelude losing power once warm 

zardozrocks wrote in
399d92c5d8f0 RemoveThis @b15g2000hsa.googlegroups.com:

>> Hi,
>> Intake. You can hook up vacuum gauge.
>
> Thanks for the response!
>
> Wouldn't that problem be evident even when the car is cold? Any links
> or advice on how to test or where to buy a vacuum gauge?

Harbor Freight has vac gauges at "low cost".

How many miles on the car? O2 sensors last about 60-100K miles.
OEM are the best.

--
Jim Yanik
jyanik
at
kua.net
 >> Stay informed about: 1987 Honda Prelude losing power once warm 

"Elle" wrote in




>
> Based only on reading here and a bit of googling, I'd also
> investigate whether the catalytic converter was partly
> plugged. Google on same for more info. Of course, then the
> big question is how it got plugged. Related to the EGR
> system?
>
> Keep checking back. Others with more expertise will post.
>
> Elle
> Original owner and now sole mantainer, 1991 Civic
>
>
>

If the cat was restricting,it would affect running ALL the time,not just
after warmup.

--
Jim Yanik
jyanik
at
kua.net
 >> Stay informed about: 1987 Honda Prelude losing power once warm 

"Jim Yanik" wrote
> "Elle" wrote
>> Based only on reading here and a bit of googling, I'd
>> also
>> investigate whether the catalytic converter was partly
>> plugged. Google on same for more info. Of course, then
>> the
>> big question is how it got plugged. Related to the EGR
>> system?
>
> If the cat was restricting,it would affect running ALL the
> time,not just
> after warmup.

I think I understand what you're saying, ("If it's plugged,
it's plugged! Even partly plugged... ), but from my reading,
the symptoms of a partly plugged cat converter become more
manifest with, say, acceleration and warmup.

http://www.aa1car.com/library/converter.htm, among other
sites, has some stuff on how temperatures yada affect cat
converter operation.
 >> Stay informed about: 1987 Honda Prelude losing power once warm 

zardozrocks wrote:
> I have a 1987 Honda Prelude 2.0 SI. It's the fuel-injected model. If
> the car is cold, it will start up immediately and runs great - i can
> lay a patch of rubber. It will run perfectly immediately following a
> cold start. Once the car has traveled a few miles, however it starts
> to lose power quite dramatically as I attempt to rev it up past about
> 2000 RPM as though it were starving for fuel or air or something. The
> problem will happen in any gear but seems a teeny bit more pronounced
> in the higher gears. Around this time, the PGM-FI light comes on on
> the dash.
>
> I've been looking at this problem for some time now and I have had
> some repairs done:
> * rebuilt/replaced fuel injectors
> * new fuel pump
> * new air/fuel/oil filters
> * replaced EGR valve
> * checked main relay for broken solder - it seems fine
>
> After posting here previously someone told me to check the ECU codes.
> The ECU code that is blinking is code #12 which for my car means a
> problem with the EGR system. When I took the car in for repairs last
> January to a small shop, the mechanic claims he replaced the EGR valve
> so I'm inclined to rule that out.
>
> Any hints on what it could be? Would a clogged oxygen sensor result
> in the ECU sending code 12? Any advice would be much appreciated! I
> MUST fix this problem and simply cannot afford expensive repairs.
>


You left out the mileage on this vehicle. How many miles on it?

JT
 >> Stay informed about: 1987 Honda Prelude losing power once warm 

Tony Hwang wrote:
> zardozrocks wrote:
>>> Hi,
>>> Heat/cold expand/shrink things. You already done quite a few rmedial
>>> tries. Checking vacuum for proper level won't hurt.
>>> Also checking all the ground point like fuel pump ground joint is
>>> good idea.
>>
>>
>> OK I'll buy the heat expansion/contraction, but I'm also wondering if
>> that will solve the car complaining about the EGR problem (code 12 on
>> the ECU).
>>
>> Most importantly, HOW do I check for a vacuum level on the intake
>> manifold? Got any links or suggestions?
> Hi,
> Take a minute and think about how EGR valve operates. Manifold vacuum
> does many things.

I'm wondering, does it also operate the EGR valve, like it does in my
carb'd '87 Accord, via a vacuum diaphragm? There could be a leak in
that vacuum line or even the diaphragm itself, and the leak is only
presenting itself once the car warms up enough to activate the EGR.
 >> Stay informed about: 1987 Honda Prelude losing power once warm