My first (and last I hope !) backfire

[plissken97]

Hi guys,

I'm Julien, I live in France and I owned for 4 years now a beautiful black 1990 ZR-1.

I made this backfire last friday...
My SES light came on.
I got 3 fault codes after my diagnosis : H33 H45 H65.
I solved 2 codes which were the H33 and H65 by putting in place the MAP sensor hose at the back of the plenum.

Unfortunately, it remains my SES light with a H45 code.
It says "Oxygen Sensor (System Rich)".

Can you help me to solve this issue ?

Thanks a lot.

Julien

[tccrab]

Julien:

The backfire might have popped off the pvc hoses when it popped off the hose on the Map sensor.
Also check the fuel regulator vacuum hose, it lives on the bottom of the fuel pressure regulator.
And your Map sensor might be still leaking a little, especially if the hose has gotten soft over the years.
If the Map sensor isn't working right, it will cause the motor to run rich will cause the codes you're still seeing.

https://www.jerrysgaskets.com/hose-m...ew-90-95-13d4/

Crabs

[plissken97]

Hi Crabs, and all the members,

Thanks for your reply.

I double-checked all these hoses, and they are okay. I noticed that when I turn the ignition on without starting the V8, the vacuum pump on the passenger side, near the front right wheel, keeps running : it starts/stops 3 secondes then restarts/restops etc.

However, I decided to start the engine, and it runs very well. There's no SES light, and the car seems to be in great condition (the car idle is ok : 700/750 rpms), although I haven't driven it on the road yet due to the bad weather in Paris in order to be sure that all the horsepower are delivered.
I ran another diagnostic test and there are no more codes.

I am a bit worried about the vacuum pump running continuously.

If anyone has any input, I'd appreciate it.

Thanks a lot et thank you all.

Julien

[A26B]

Sounds like you have a vacuum leak, likely in the Secondary Port Throttle (SPT) System. There is a rubber hose connection, near the alternator, in the hard plastic line from the vacuum pump to the SPT system. Disconnect the line there.

Key on- Engine off, put finger on end of hose going to the vacuum pump to isolate the pump from the SPT system. The pump should only run a short time and stop until you release your finger. If this is the case, the vacuum leak is in the SPT system. Re-connect the hard plastic line.

Before removing the plenum, Remove the vacuum line from the pipe located on the driver side of the plenum at the center. Key on, Engine off, plug the removed hose. If the vacuum pump stops and/or the stop cycle is significantly longer between starts, the problem is likely the check valve under the plenum is faulty. If not, then the leak is under the plenum.

[plissken97]

Thanks Jerry for your feedback, this is really appreciated.
I will try your tips.

Originally Posted by A26B

Before removing the plenum, Remove the vacuum line from the pipe located on the driver side of the plenum at the center. Key on, Engine off, plug the removed hose. If the vacuum pump stops and/or the stop cycle is significantly longer between starts, the problem is likely the check valve under the plenum is faulty. If not, then the leak is under the plenum.

In these both cases, whatever the problem is, it seems that it is are located under the plenum !

[A26B]

Originally Posted by plissken97

Thanks Jerry for your feedback, this is really appreciated.
I will try your tips.
In these both cases, whatever the problem is, it seems that it is are located under the plenum !

True, but as a temporary measure, if the check valve is bad, you can install a good check valve on the outside of the plenum, between the pipe & hose, until you get around to pulling the plenum

[plissken97]

mod?les

ChatGPT Automatique

Partager

User
Vous avez dit :
Before removing the plenum, Remove the vacuum line from the pipe located on the driver side of the plenum at the center. Key on, Engine off, plug the removed hose. If the vacuum pump stops and/or the stop cycle is significantly longer between starts, the problem is likely the check valve under the plenum is faulty. If not, then the leak is under the plenum.
ChatGPT a dit :
ChatGPT
It sounds like you are following a diagnostic process for identifying a vacuum leak or faulty check valve in an engine with a plenum. Here's a breakdown of the steps you are referring to:

Locate and Remove the Vacuum Line:

Before removing the plenum, identify the vacuum line connected to a pipe located on the driver side, in the center of the plenum.
Remove this vacuum line carefully.
Key On, Engine Off:

Turn the ignition to the "on" position without starting the engine (this is referred to as KOEO - Key On, Engine Off). This allows the vehicle's systems, such as the vacuum pump, to activate without the engine running.
Plug the Removed Hose:

Use your finger or another plug to seal off the hose that you removed. This prevents any vacuum leaks through that hose while testing the system.
Observe the Vacuum Pump:

Pay attention to the behavior of the vacuum pump. If the pump stops running or the time between its cycles (on and off) is significantly longer:
Check Valve Faulty: This indicates that the check valve under the plenum is likely faulty.
Leak Under Plenum: If there is no change, then the leak is likely occurring under the plenum itself, and further inspection or removal of the plenum may be necessary to locate the problem





Vous avez dit :
A TRADUIRE EN FRAN?AIS
ChatGPT a dit :
ChatGPT
Avant de retirer le pl?num, retirez la durite de d?pression du tuyau situ? du c?t? conducteur du pl?num, au centre. Mettez le contact sans d?marrer le moteur, puis bouchez la durite retir?e. Si la pompe ? vide s'arr?te et/ou si le cycle d'arr?t est significativement plus long entre les d?marrages, le probl?me est probablement d? ? une soupape de retenue d?fectueuse sous le pl?num. Sinon, la fuite se trouve sous le pl?num.






Vous avez dit :
Before removing the plenum, Remove the vacuum line from the pipe located on the driver side of the plenum at the center. Key on, Engine off, plug the removed hose. If the vacuum pump stops and/or the stop cycle is significantly longer between starts, the problem is likely the check valve under the plenum is faulty. If not, then the leak is under the plenum.
ChatGPT a dit :
ChatGPT
It looks like you're describing a procedure to troubleshoot a vacuum system issue, likely related to a check valve or a vacuum leak in an engine.

Breakdown of the Procedure:
Remove the Vacuum Line:
Before removing the plenum, locate the vacuum line that is connected to a pipe on the driver?s side





Vous avez dit :
traduis moi en fran?ais cette phrase :
ChatGPT a dit :
ChatGPT
Avant de retirer le pl?num, retirez la durite de d?pression du tuyau situ? du c?t? conducteur du pl?num, au centre. Mettez le contact sans d?marrer le moteur, puis bouchez la durite retir?e. Si la pompe ? vide s'arr?te et/ou si le cycle d'arr?t est significativement plus long entre les d?marrages, le probl?me vient probablement de la valve anti-retour sous le pl?num. Sinon, la fuite se trouve sous le pl?num.






Vous avez dit :
comment traduire en anglais
ChatGPT a dit :
ChatGPT
Pour traduire une phrase en anglais, il faut identifier le sens de chaque ?l?ment dans la langue source et les rendre de mani?re correcte en anglais. Voici quelques conseils pour une bonne traduction :

Conserver le sens original : Assurez-vous de bien comprendre le sens global de la phrase en fran?ais avant de commencer ? la traduire.
Adapter les expressions idiomatiques : Certaines expressions ne se traduisent pas litt?ralement. Cherchez des ?quivalents en anglais si n?cessaire.
Choisir le bon temps et la bonne structure grammaticale : Faites attention ? la conjug





Vous avez dit :
est ce que la phrase suivante est correcte en anglais
ChatGPT a dit :
ChatGPT
Bien s?r ! Je suis pr?t ? v?rifier la phrase en anglais pour vous. Veuillez la partager, et je vous dirai si elle est correcte ou non.






Vous avez dit :
I do not losing
ChatGPT a dit :
ChatGPT
La phrase "I do not losing" n'est pas correcte en anglais. Voici la correction :

Correct version : "I am not losing" ou "I do not lose," selon le contexte.
Explication :
"I am not losing" : Utilis? pour une action en cours ou un ?tat qui se produit maintenant (pr?sent continu).
"I do not lose" : Utilis? pour exprimer un fait g?n?ral ou une habitude (pr?sent simple).
Choisissez la version qui correspond ? ce que vous voulez dire.






Vous avez dit :
que cela signigie t il
ChatGPT a dit :
ChatGPT
Voici la signification des deux phrases :

"I am not losing" : signifie "Je ne suis pas en train de perdre." Cela d?crit une action qui se passe en ce moment m?me, en cours.

Exemple : Pendant un match, vous pouvez dire "I am not losing" pour signifier que vous n'?tes pas en train de perdre ? ce moment pr?cis.
"I do not lose" : signifie "Je ne perds pas." Cela d?crit une g?n?ralit? ou une habitude. Cela peut aussi signifier que vous ne perdez jamais ou rarement.

Exemple : "I do not lose easily" signifie "Je ne perds pas facilement."
Cela d?pend donc du contexte pour choisir l'une ou l'autre des phrases.






Vous avez dit :
comment traduire je n'aime pas perdre
ChatGPT a dit :
ChatGPT
La traduction de "je n'aime pas perdre" en anglais est :

"I don't like to lose" ou "I don't like losing".

Les deux versions sont correctes, et le choix d?pend de la pr?f?rence de style.






Vous avez dit :
peux-tu me corriger cette phrase:
ChatGPT a dit :
ChatGPT
Bien s?r ! Veuillez me donner la phrase, et je la corrigerai pour vous.






Vous avez dit :
So I checked your tips and :
- it comes from the Throttle System,
- it does not come from the check valve,
As a conclusion it comes from under the plenum...

But after I unplugged/plugged the hose close to the alternator (the one which goes to the vacuum pump) I've noticed that the vacuum pump starts ans stops every 10 seconds approximately. Not as fast as before.

Do you think I still have a leak ?

Thanks a lot.

Julien
ChatGPT a dit :
ChatGPT
Voici une version corrig?e de votre phrase en anglais :

Corrected Version:

So I followed your tips and:

The issue comes from the Throttle System.
It does not come from the check valve.
In conclusion, the problem seems to come from under the plenum...

However, after I unplugged/plugged the hose near the alternator (the one that goes to the vacuum pump), I noticed that the vacuum pump now starts and stops every 10 seconds approximately, not as fast as before.

Do you think I still have a leak?

Thanks a lot.

Julien